Forensic Science History and Nature PDF

Module 1: History and Nature of Forensic Science Page 1 Module Overview Introduction Modern day forensic science has developed into a series of highly specialized disciplines that rely on an array of sophisticated technology for the investigation of everything from biological fluids to fibers and drugs. Forensic science has developed over centuries, drawing upon techniques and knowledge from many different aspects of science and engineering and applying them to the detection and investigation of crimes. This module outlines the development of forensic science from its early beginnings to the present. The different disciplines included in this field are also introduced. Objectives At the end of this module the student will: Understand what forensic science is Have an appreciation for the historical development of this applied science Understand the different disciplines of forensic science Understand how the use of scientific principles may attenuate bias Module 1: History and Nature of Forensic Science Page 2 What is Forensic Science? What is Forensic Science? Deﬁnition of Forensic Science Forensic science is the application of scientific principles and technology to the legal process. It essentially involves the characterization and examination of evidence. Forensic science draws upon and applies the principles and methods of all the traditional sciences and engineering, including physics, chemistry and biology. Classiﬁcation and Use of Forensic Science Most operational forensic laboratories classify their sections according to the type of testing performed. These can generally be listed as follows: Controlled substances Serology DNA Trace Chemistry Firearms Toolmarks Questioned Documents Latent Prints Toxicology These classifications may reflect the organization of the laboratory. For example examination of Toolmarks is often associated with the Firearms section because they share the same approach to the comparison of unique and class marks on physical objects. Forensic evidence can be classified in a number of different ways: It may be associative in nature, which is linking people, places or objects. The well-known Locard Principle ("Every contact leaves a trace") relates to associative evidence. Associative evidence may be sub-divided, for example fingerprints or DNA. However, much of the evidence that comes from a typical crime laboratory is not associative, it is inceptive. That is it addresses the issue of whether an offence has occurred. Controlled substance analysis and alcohol testing are examples of inceptive evidence. When dealing with associative evidence we also need to consider the results. Here there is a link with the falsification approach (https://explorable.com/falsifiability) to basic science. Testing may produce evidence to exclude an association (DNA types in recovered sperm may differ from those of the suspect). If they do not exclude the suspect then we are left with corroborative evidence that supports but does not prove the hypothesis of association. Case Study Two suspects were implicated in a murder involving a blunt force trauma. Bloody clothing was found on the floor of an abandoned apartment approximately 12 hours post-incident. DNA testing was completed on a brown coat. Blood evidence on the coat included the victim as a contributor. Wearer DNA from the collar excluded the victim but both suspects and an unknown person could not be excluded as contributors. Because of the mixture, no definitive conclusion regarding who may have been wearing the jacket could be made. Aside from the timeline and chain of custody issues, the jacket was not inculpatory or exculpatory evidence for those alleged to have committed the crime. Module 1: History and Nature of Forensic Science Page 3 The History of Forensic Science The History of Forensic Science The databases, techniques and tests used routinely in forensic investigations have been constructed, and refined in a development process that, for some disciplines has taken centuries. The growth of the field of forensic science has been steered by the worldwide development of a number of specialty or sub specialized scientific disciplines. http://www.forensicsciencesimplified.org/ (http://www.forensicsciencesimplified.org/) and then click on “Professions” and “Job Outlook” (scroll down and look for a menu bar on the left side of the screen) for a more detailed look at the careers available in forensics. (http://www.forensicscience.org/resources/careers-in-forensic-science/) Milestones in Forensic Science 6th century Certain aspects of forensic medicine were first documented in China. ≈ 1247 Chinese manuscripts provided methods to determine death by drowning or strangulation, from death by natural causes. 1800’s The 1800’s saw the beginning of questioned document examination in Europe. At the outset, photographers who tried to broaden their expertise by incorporating document comparison conducted document examination. This actually led to slowed acceptance of the profession as many highly publicized mistakes were made. 1800-1810 Mateu Orfila, was one of the first experts to provide reliable scientific evidence in a criminal trial, and conducted academic studies in toxicology and is credited with establishing toxicology as an organized branch of forensic science. Orfila and associates developed the first chemical test to detect arsenic, and produced the first scientific treatise on the detection of poisons. The first documented provision of legal testimony by legal medical experts comes from this era. 1820-1829 After studying methods of blood and semen identification, Orfila developed a series of chemical tests for semen identification laying the foundations for some of today's routine tests 1830’s Henry Goddard, of Scotland Yard, first used bullet comparisons to provide evidence leading to the arrest of a murderer. 1861 Rudolph Virchow reported the first forensic investigation of human hair in and determined that a questioned hair from a crime suspect was indistinguishable from that of his victim. 1870-1879 William Herschel proposed the application of Fingerprinting for personal identification. Henry Faulds, a Scottish physician, residing in Japan used latent prints from a crime scene to identify a burglar. 1890-1899 Dr Alexandre Lacassagne, at the University of Lyons, was the first to associate bullets with a specific gun, and as a professor of forensic medicine was one of the first to study blood spatter patterns Juan Vucetich, an Argentinean police official established his own fingerprint classification system, based on his own research data and fingerprint pattern types described by Francis Galton. Francis Galton published first treatise on systematic identification of fingerprints in some 30 years after Henry Faulds published paper in Nature describing use of fingerprinting to identify someone. In France, Victor Balthazard, medical examiner for the city of Paris, studied probability models for fingerprints; bullet comparison, animal hairs, and blood spatter patterns, Hans Gross of Austria furthered criminalistics by applying scientific knowledge and methods for the interpretation and analysis of physical evidence in crime investigation, and established a journal dedicated to forensic science. Works of Arthur Conan-Doyle published at this time suggested that soil collected on a person at a crime scene could be used as evidence to place that person at that location. 1900’s Alphonse Bertillon (1853 - 1914) - developed the most significant and earliest personal identification system. Bertillon’s anthropometrics system used a series of body and facial measurements, to identify habitual criminals. Although Bertillon opposed the introduction of fingerprinting, he was the first person in Europe to use latent prints to solve a criminal case Sir Edward Richard Henry was appointed head of Scotland Yard and implemented his fingerprint classification scheme, which eventually replaced anthropometry in Europe and North America. Paul Jesrich acquired photomicrographs of bullets for comparison purposes 1900-1909 The first recorded use of botanical evidence was in Germany in by Dr George Popp who presented one of the first examples of evidence in a criminal case using botanical materials. Hugo Marx, an official in the State Medical and Prison Medical Examiners office in Berlin prepared a dissertation on the value of forensic hair examination, following a textbook published by the founder of the Vienna school of forensic medicine that contained a chapter on the investigation of hair. 1910-1920 Edmund Locard set up the first police crime laboratory in Europe, in Lyons; the location of today's Interpol. Victor Balthazard and Marcelle Lambert produced "Le poil de l'homme et des animaux (the Hair of Man and Animals)" in, detailing the use of microscopical analysis to compare and observe morphological features Victor Balthazard published the first scientific article on the significance of bullet markings and their relation to bullet individualization. Questioned document testimony in US courts was eventually accepted in 1913. Leone Lattes, professor at the Institute of Forensic Medicine in Turin Italy first developed antibody tests for the ABO blood groups 1920-1929 Luke May developed and applied analyses for toolmark comparison. The first US police crime laboratory in Los Angeles was established. Charles Waite catalogued information regarding weapon manufacture, and with collaborative efforts by Goddard, Gravelle and Fisher, developed comparison microscopy for bullet comparison. Edmund Locard made the observation that it was almost impossible for anyone to participate in any activity without removing soil or dust particles from the site by contaminating their person or vehicle. 1930-1939 1930’s Franz Josef Holzer, an Austrian scientist, developed the absorptioninhibition ABO typing technique that was to become used routinely in forensic science. John Glaister published a work containing 1700 photomicrographs that show the structure of hair of humans and other mammals and their relation to criminal investigation. The FBI crime lab was established in 1932 1940-1949 Lansteiner first described Rhesus blood groups The Lewis, Kell and Duffy blood group systems were discovered. 1950-1959 The American Academy of Forensic Science was formed, followed by the institution of the Journal of Forensic Science. Hirschfield was the first to identify the polymorphic nature of group specific component (GC) 1960-1969 The polymorphic nature of erythrocyte acid phosphatase (EAP), Phosphoglucomutase (PGM) and adenylate cyclase (AK) was determined which resulted in the development of electrophoretic techniques for haptoglobin typing and isoenzyme testing, by Culliford and Wraxal of the Metropolitan Police laboratory in London. 1970-1979 More isoenzyme grouping systems were discovered in the early including esterase D (ESD) and red cell Glyoxylase (GLO) 1980-1990 Sir Alex Jeffreys and colleagues developed the techniques for profile analysis of DNA. In 1985 their achievements their were published in Nature. As a result of collaborative efforts between the British Home Office Forensic Science Service, and Jeffreys, the murderer of two English schoolgirls was identified. DNA profiling was introduced to the US criminal courts for the first time, but admissibility was challenged resulting in the development and implementation of accreditation, standardization and quality controls for DNA and forensic laboratories. As mentioned earlier, Forensic Science draws upon a wide range of scientific specialties and disciplines. The primary consideration however is the identification, individualization or classification, of physical evidence. In some cases, this may only be possible after conducting chemical or scientific tests. Types of evidence that require testing to ensure accurate identification include: Bloodstains Body fluids Drugs Arson accelerants and other chemicals The identification of unknown substances or objects may be achieved by comparing their characteristics with those of known standards, previously established criteria or database information. In the forensic examination of hairs and fibers for example, parameters such as fiber type, form, dye composition, color, species or anatomical origin, are used as characteristics for such identification. The ultimate goal of the identification process in forensic science is individualization: to say that a particular piece of evidence originates from a specific locus, scene or person. In reality, few types of evidence can be unequivocally individualized to the extent of fingerprint and DNA evidence. More typically, evidence if appropriately identified, can be said to be consistent with originating from a particular source, site or individual. Many of the classical databases, techniques and tests now routinely used in forensic identification have been constructed, developed and refined, in a process which for some disciplines has taken centuries. The Linkage Principle TOP Module 1: History and Nature of Forensic Science Page 4 Forensic Medicine and Toxicology Forensic Medicine and Toxicology Arguably the earliest documented forensic specialty is forensic medicine which is now considered as a separate discipline to forensic science. Also known as legal medicine or medical jurisprudence, it is the application of medicine and medical science to the legal process. Records indicate that the first documented dissertation on forensic medicine was written in China in the 6th century. Although this work was apparently lost, a second Chinese manuscript still exists. Completed in 1247, the "Shsi Yuan Lu (The Washing Away of Wrongs)", provides what is thought to be the first discussion of medicine in a legal context, and provides details on distinguishing suspicious deaths by drowning or strangulation, from death by natural causes. However it was not until the late 1700's that the first appearance of legal medicine experts in the courtroom was documented. Advances in chemistry at the end of the 18th century, paved the way for the development of modern toxicology. Closely related to forensic medicine, forensic toxicology focuses on the identification and quantitation of toxic substances in body fluids and tissues and the subsequent determination of the role any such agent may have played in contributing to or causing death. While the origins of forensic toxicology lie in the detection of deliberate poisonings, these days most cases deal with some form of drug or alcohol abuse. One of the most influential people in the development of toxicology was Mateu J. Bonaventura Orfila (1787- 1853). He was born in Minorca, Spain and eventually became dean of the Faculty of Medicine of Paris, a powerful and influential position inside the French medical community. Orfila is considered to be one of the first expert witnesses to provide reliable scientific evidence in a criminal trial. His academic studies went a long way toward the acceptance of toxicology as a scientific discipline within the developing field of forensic medicine. Orfila and co-workers are credited with developing the first chemical test to detect arsenic, which was prevalent at that time as a poison. However, it was James Marsh, a Scottish chemist, who was considered the first to provide toxicological evidence supporting arsenic detection for a legal trial around 1836. The Lafarge case, also examined by Orfila, is documented as the first case in which the defense called an opposing expert, Francois Vincent Raspail, in an attempt to refute the scientific evidence of the prosecutions expert witness. And so the present day system of forensic experts appearing for the defense and prosecution was born. http://www.nlm.nih.gov/visibleproofs/exhibition/rise.html (http://www.nlm.nih.gov/visibleproofs/exhibition/rise.html) Module 1: History and Nature of Forensic Science Page 5 Personal Identification: Forensic Odontology & Fingerprints Personal Identiﬁcation One aspect of forensic and criminal investigation that continues to be of major importance and is the subject of a great deal of development efforts is personal identification. There are several subspecialties within this discipline that are used for forensic purposes. Forensic Odontology Forensic odontology uses dental records to aid in human identification. This type of identification process is often called for in the identification of unrecognizable bodies, for example after a mass disaster, and in the identification and comparison of bite marks. Also facilitating personal identification is the use of forensic anthropology. This discipline is primarily associated with the identification of skeletal remains, and over recent years, a number of databases have been developed that catalog differences in physical structure of the body as a function of sex and race. Alphonse Bertillon first developed the most significant personal identification system, at the end of the 19th century. Bertillon’s system of anthropometry involved a series of body and facial measurements, and was developed to establish a process of identification of habitual criminals. The system, also known as Bertillonage, was devised in Paris and applied worldwide. It is now considered that this system of identification cannot be utilized to uniquely identify one person as being distinct from all others. Although the concept of anthropometry was considered theoretically possible, in practice, inconsistency in measurement techniques decreased the discriminating ability of the system. Despite this, Bertillon's system is still considered to have made a significant contribution to the development of forensic science, representing one of the first examples of the use of individualization for criminal investigation. Anthropometric systems were replaced as the science of fingerprinting was developed and the value of fingerprinting in personal identification and individualization was acknowledged. http://www.nyu.edu/greyart/exhibits/police/html/mug.html (http://www.nyu.edu/greyart/exhibits/police/html/mug.html) Case Study Theodore ‘Ted’ Bundy is known as one of America’s most vicious and prolific serial killers. Prior to his execution in 1989, he confessed to 30 murders, but there are thought to be more. During trial, his ultimate undoing would be testimony from forensic odontologist Dr. Richard Souviron, who stated that a bite mark found on victim Lisa Levy was a ‘match’ to Bundy’s dentition. See: https://www.dental.umaryland.edu/museum/exhibits/online-exhibits/forensicodontology/the-most-infamous-bite-mark-case/ (https://www.dental.umaryland.edu/museum/exhibits/online-exhibits/forensic-odontology/themost-infamous-bite-mark-case/) The vast majority of cases that involve the use of a forensic odontologist attempt to identify human remains when friction skin no longer exists. Working alongside a forensic anthropologist, the odontologist will use known radiographs of the victim to attempt to match the dentition pattern and dental work. See: http://abfo.org/resources/abfo-manual/ (http://abfo.org/resources/abfo-manual/) Fingerprints One of the most widely used identification techniques is fingerprinting. Bertillon is credited with being the first to use latent prints in a criminal case, despite the fact that he opposed its introduction as an identification tool in favor of his anthropometric system. Bertillon was also the first to use systematic crime scene photography for recording a scene. The development of fingerprinting for criminal identification purposes was originally the initiative of William Herschel, a British civil servant residing in India around 1877. Henry Faulds, a Scottish physician working in Japan around the same time, recognized the value of latent prints from a crime scene. The use of fingerprints in identifying a criminal was subsequently published in the journal Nature, and Faulds continued to use fingerprints to identify a Tokyo burglar in 1880. As a result of his own studies and fingerprint pattern types described by Francis Galton, Juan Vucetich, an Argentinean police official, set up his own fingerprint classification system in 1891. In 1892, Galton published "Fingerprints", the first text on the use of fingerprints in personal identification and crime investigation and devised the first scientific methods for the classification of fingerprint patterns. Several years later, Sir Edward Richard Henry, another British civil servant in India, devised a fingerprint classification scheme, cataloging sets of fingerprints that could be retrieved for identification purposes. Subsequently a fingerprint classification system was developed that would replace anthropometry in Europe and North America. This system was implemented in Europe when Henry was appointed head of Scotland Yard in the early 1900’s. At the same time, in the United States, DeForrest initiated the first systematic use of fingerprints in personal identification. More recently, the Federal Bureau of Investigation's (FBI's) Automated Fingerprint Identification System (AFIS) was introduced as a means of providing identification services to US law enforcement communities. https://www.ncjrs.gov/pdffiles1/nij/225326.pdf (https://www.ncjrs.gov/pdffiles1/nij/225326.pdf) Next Generation Identiﬁcation In September 2014, the FBI announced its newest identification program, NGI. This program is slated to eventually replace IAFIS as the premiere identification tool nationwide. It encompasses a wide array of biometric identification methods including scars, tattoos, facial recognition, decreased response times for fingerprint and palm print comparisons and voice and iris identification parameters. See: http://www.fbi.gov/about-us/cjis/fingerprints_biometrics/ngi us/cjis/fingerprints_biometrics/ngi) (http://www.fbi.gov/about- Module 1: History and Nature of Forensic Science Page 6 Criminalistics Criminalistics Criminalistics is a fairly generic term that is often used as a synonym for forensic science. However criminalistics is considered to include all areas of trace evidence, such as soil, glass, hairs, fibers, blood and other body fluids including, saliva, sweat, semen and vitreous humor. It also includes arson, explosives, drug identification and investigation, interpretation of pattern and imprint evidence. In addition to his toxicological efforts, Orfila was responsible for initiating early studies on blood and semen identification. This work laid the foundation for the development of some of the routine tests in use today. Recognizing that the extraction of intact spermatozoa from seminal stains was extremely difficult, Orfila developed a series of chemical tests for semen identification. Subsequently other workers established that microscopical examination of semen stains provided the most useful forensic information. In 1891, the Austrian Hans Gross first promoted the concept of criminalistics by applying scientific knowledge and methods to the interpretation and analysis of physical evidence for crime investigation. Gross, who was also a legal expert saw the function of criminalistics as the complementary collaboration of various forensic specialists with appropriate scientific backgrounds for the examination and interpretation of physical evidence. Gross was also responsible for the introduction of one of the first journals dedicated to forensic sciences. In France, Victor Balthazard and Edmond Locard conducted similar work. Balthazard, a medical examiner for the city of Paris, also performed studies on probability models for fingerprints; bullet comparison, animal hairs, and blood spatter patterns. In 1910, Locard set up the first police crime laboratory in Europe, in Lyons, the location of today's Interpol. He is recognized for the inception of the Locard Exchange Principle: "Every contact leaves a trace", the basic tenet of forensic science. Also during the 1920's, Luke May, developed and applied striation analysis for tool mark comparisons, incorporating statistical analysis into his methodology. In the latter part of the 1920’s, August Vollmer, of the Los Angeles County Sheriffs department, developed the first United States police crime laboratory. The FBI crime lab was subsequently established in 1932 and five years later, Paul Kirk set up the first academic criminalistics program in the United States at the University of California, Berkeley. In 1950, the American Academy of Forensic Science was formed, with the subsequent introduction of the Journal of Forensic Science. Today, there are approximately 6,400 members of the AAFS. Additionally, the International Association for Identification has approximately 6,700 members and will celebrate its Centennial in 2015. The IAI publishes the Journal of Forensic Identification. The AAFS and IAI have worked in tandem to provide practitioners with an annual forum and peer-reviewed journals to present new and innovative techniques, case studies and breakthroughs relevant to all aspects of forensic science. In October 2014, the National Institute of Standards and Technology (NIST) announced the members of the Organization for Scientific Area Committees (OSAC), the newest collaborative effort to codify each individual area of practice, certification requirements and update standards of practice. The new committees will meet several times a year to facilitate new ideas and guidelines. See: http://www.nist.gov/forensics/osac.cfm https://www.theiai.org (https://www.theiai.org) (http://www.nist.gov/forensics/osac.cfm) http://www.aafs.org (http://www.aafs.org) Module 1: History and Nature of Forensic Science Page 7 Ballistics and Firearm Identification Ballistics and Firearm Identiﬁcation This specialization incorporates firearm identification, comparison of bullet markings and rifling, the identification of projectiles, cartridge and shell cases, and, the determination of bullet trajectories and damage. The development of this field began around 1835 when Henry Goddard, working for Scotland Yard, first used bullet comparisons to provide evidence leading to the arrest of a murderer. The comparison revealed a flaw in the bullet that could be traced back to a flaw in the original bullet mold. Nearly fifty-five years later, Dr Alexandre Lacassagne, professor of forensic medicine at the University of Lyons, associated bullets with a specific gun, by comparing striations etched on the bullet recovered from a homicide victim and striations from the gun barrel from which the bullet was fired. Lacassagne was also one of the first to study the nature of blood spatter patterns. The discipline further developed around 1900, when Paul Jesrich, took photomicrographs of bullets for comparison, and illustrated the use of this technique for the possible individualization of minutiae. Not until 1913, did Victor Balthazard, publish the first scientific article on the significance of bullet markings and their relation to bullet individualization. Further developments occurred during the 1920's, as Charles Waite first catalogued information regarding weapon manufacture, and together with Goddard, Gravelle and Fisher, further developed the technique of comparison microscopy for bullet comparison. http://www.firearmsid.com/A_historyoffirearmsID.htm (http://www.firearmsid.com/A_historyoffirearmsID.htm) Module 1: History and Nature of Forensic Science Page 8 Questioned Documents Questioned Documents Questioned document examination entails the comparison and interpretation of handwriting; materials generated from typing, printing, facsimiles and photocopying; and the analysis and aging of paper, inks and materials used to produce documents. Such techniques have featured in numerous high profile cases such as Jon Benet Ramsey and the Hitler Diaries. Francois Demelle in France reportedly published the first study on questioned document examination in 1609. Only after improvements in photography in the 1800's however, did document examination gain credibility in Europe. Photographers at that time attempted to broaden their professional expertise by providing services that incorporated document comparison. Highly publicized mistakes however delayed the acceptance of document examination by the legal system. One such mistake involved the acclaimed Alphonse Bertillon. In the Dreyfuss case, he testified that the accused had written a document that was the basis for the charge of treason. The accuser’s innocence was later proven. Questioned document examination was also slow to be accepted in the United States partly because of the existence of old English laws that stated that writings were inadmissible as standards for comparison unless the writings were in evidence in a prior case. Testimony on questioned documents in US courts eventually became a reality in 1913 after enactment of Section 1731, Title 28 US Code. The code states that: "the admitted or proved handwriting of any person shall be admissible for purposes of comparison to determine genuineness of other handwriting attributed to such person". Today, the Questioned Documents Unit of the FBI Crime laboratory examines all aspects of documentary evidence including hand printing, typewriter ribbons, printers, watermarks, erasures, alterations, obliterations, safety paper, charred paper, graphic arts, plastic bags, and product tampering. The unit maintains the database files such as the Anonymous Letter File, Bank Robbery Note File, National Fraudulent Check File, Office Equipment File, and Watermark File. http://www.qdewill.com (http://www.qdewill.com) Module 1: History and Nature of Forensic Science Page 9 Soil Examination Soil Examination The main contributor to the development of forensic soil and particulate examination was, again, Edmond Locard. In 1929, he made the observation that it was almost impossible for anyone to participate in any activity without removing soil or dust particles from the site as a result of contamination of ones body, clothes, tools or vehicle. However, Locard credited the fictional character Sherlock Holmes with the idea that botanical or earth materials could have important evidential value. Arthur Conan Doyle’s books, published toward the end of the 19 th century, suggested that soil collected on a person at a crime scene could be used as evidence to place that person at a particular location. The first recorded use of this type of evidence was in Germany in 1904, by Dr George Popp who developed and presented what is thought to be the first example of evidence in a criminal case using botanical materials. Throughout the 1920's Popp continued to pioneer the use of botanical identification in forensic work. https://web.mst.edu/~rogersda/forensic_geology/Geoforensics%20Case%20Histories.htm (https://web.mst.edu/~rogersda/forensic_geology/Geoforensics%20Case%20Histories.htm) Case Study A body was located in a shallow grave. The victim was last seen leaving a local store 22 days prior to the discovery. After numerous search warrants were carried out, blood was found in the suspect’s SUV as well as a receipt for a shovel and duct tape. A subsequent search of an apartment complex property yielded a shovel, located underneath a walk-over between two buildings. Soil samples were collected from the spade, apartment complex and the area where the victim was buried. Microscopic examination of the samples found unique properties that matched the shovel and victim’s location and excluded the apartment complex soil. Further investigation included video surveillance of a Lowe’s Home Improvement store that showed the suspect purchasing a shovel and duct tape just prior to the disappearance of the victim. This evidence was presented at trial and the male friend was found guilty of firstdegree murder. Module 1: History and Nature of Forensic Science Page 10 Identification and Association of Human Hair Identiﬁcation and Association of Human Hair Rudolph Virchow, a professor and prosecutor in Berlin, Germany, reported the first forensic investigation of human hair in 1861. Virchow established that a hair from a particular crime suspect was indistinguishable from that of the victim. By the early 1900's the significance of hair evidence in criminal investigations was routinely criticized and scrutinized by a number of medico-legal experts. In 1906, Hugo Marx, an official in the State Medical and Prison Medical Examiners office in Berlin wrote a dissertation on the value of forensic hair examination and its role in personal identification. A textbook published at the turn of the century, from the founder of the Vienna school of forensic medicine also contained a chapter on the investigation of hair. In 1910 Victor Balthazard and his associate, Marcelle Lambert produced "Le poil de l'homme et des animaux (the Hair of Man and Animals)". In this work they described techniques similar to those still employed for hair comparisons. These rely heavily on microscopy to observe and compare morphological features. In 1931, John Glaister, published a study of mammalian hairs and wool and their relevance to criminal investigation. The work contains approximately 1700 photomicrographs that show the structure of hair from humans and other mammals. Paul Kirk, criminalistics professor at the University of California at Berkeley further developed the technique of hair comparison, by utilizing various physical and chemical properties in an attempt to facilitate the systematic individualization of human hair. Despite, cutting edge advances in various other specialties of forensic science, the methods, philosophy and significance of forensic hair examination have not changed greatly since the early twentieth century. https://drive.google.com/file/d/1rVxPt6ds3WGcnLE5qRPrfdjwI0Uwk8lS/view (https://drive.google.com/file/d/1rVxPt6ds3WGcnLE5qRPrfdjwI0Uwk8lS/view) Module 1: History and Nature of Forensic Science Page 11 Bias in Forensic Science Bias in Forensic Science In recent years, many studies have been completed regarding contextual effects and confirmation bias in forensic science. While debate continues regarding the actual impact bias plays in forensic analysis, it is a relevant subject that should be addressed and recognized. Contextual effects are environmental influences and past experiences that can sway our decision-making processes. While not always bad, these cognitive biases may affect our ability to remain objective when addressing evidence, patterns and possible links between sources and items. Confirmation bias is the concept of accepting conclusions of another without due diligence of the scientific process. Verification processes can be a classic form of confirmation bias because the word verification in itself is defined as “evidence that establishes or confirms the accuracy or truth of something”.1 While not a flawed concept alone, it is better practice to attempt to disprove theories than to simply render a seal of approval based upon another’s findings. Bias has been found to exist in studies on DNA interpretation, latent print analysis, forensic anthropology and bloodstain pattern analysis. Our biases work in everyday life, not just in forensic analysis. They assist us with quick decisionmaking processes and allow mental shortcuts based upon past experience. Bias is not based upon our morals, ethics or will to perform excellent work. It is a separate and unique psychological phenomenon that cannot be ‘willed away’, no matter how hard we try. In a 2005 study by Dror, Charlton and Péron2, 5 experienced latent print examiners were asked to participate in a blind test over the course of one year. Within that year during their regular casework, the participants were reissued a case that they had called a match 5 years prior. Contextual information was provided along with the reissued prints. Participants were told that the recovered latent print and known exemplar were from the Madrid bombing case that had been erroneously matched by FBI examiners, thus creating a preconceived conclusion of a non-match. Remember—these were the examiner’s own cases from 5 years prior, not the Madrid bombing prints. 1 examiner did not change their conclusion and stated the prints were a match. 1 examiner changed their mind to inconclusive. 3 examiners completely changed their conclusions from identification to exclusion. 4 out of 5 changed their opinion based solely on provided contextual information. It is important to understand that although the above study is one of many that highlights the importance of recognizing and acknowledging bias, there are ways to help minimize its effects both during and after a crime occurs; having a peer review process that attempts to disprove the posited theories rather than the approval of methodologies and by considering the use of blind verification processes. While time-consuming and tedious, these solutions could assist examiners and analysts come to conclusions that, while not completely free of bias, have taken steps to keep it to an absolute minimum. See also: http://www.psmag.com/navigation/politics-and-law/biased-forensics-experts-82712/ (http://www.psmag.com/navigation/politics-and-law/biased-forensics-experts-82712/) 1 2 Retrieved from Dictionary.com. http://dictionary.reference.com/browse/verification “Contextual information renders experts vulnerable to making erroneous identifications.” Forensic Science International 156(2006) 74-78. Module 1: History and Nature of Forensic Science Page 12 DNA Profiling DNA Proﬁling Evolving from classical serology, DNA profiling could be considered the modern day technique that revolutionized personal identification in forensic science. In the mid 1980's, Sir Alex Jeffreys developed the technique allowing the profile analysis of DNA. After publishing his achievements in Nature in 1985, Jeffreys was subsequently called upon to apply DNA testing to a criminal investigation for the first time in 1986. Together with the British Home Office Forensic Science Service, Jeffreys’ DNA profiling techniques were used to identify Colin Pitchfork as the murderer of Dawn Ashworth and Lynda Mann in Leicestershire, England. Cetus Corporation subsequently furthered the developments of DNA profiling and molecular biology techniques in personal identification with the development of the polymerase chain reaction (PCR). In 1987, not only was DNA profiling introduced for the first time to US criminal courts, but also after its admissibility was challenged, appropriate accreditation, standardization and quality controls for DNA and forensic laboratories were developed and introduced. During 1996, the FBI DNA Analysis Unit began using mitochondrial DNA analysis. This type of analysis can be applied to small or degraded quantities of DNA from hair, bones, teeth, and body fluids, allowing the examination of evidence that previously may not have been suitable for comparison. http://www.newenglandinnocence.org/ (http://www.newenglandinnocence.org/) Module 1: History and Nature of Forensic Science Accreditation Page 13 Accreditation Finally, over the last 30 years or so, several organizations have emerged that have developed guidelines and regulations assuring forensic laboratory standardization, accreditation and certification. Of the numerous organizations that exist, three have made significant impacts on the professional appearance of the field of forensic science. The American Society for Testing and Materials (ASTM) committee E-30 on Forensic Sciences was created in 1970, with the purpose of standardizing methods and terminology unique to the field. To keep pace with the rapid technological advances, standards are continuously being updated. For many years, the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB) was used as an accrediting body by many forensic laboratories to ensure the quality of their laboratories. ASCLD/LAB provided supplemental requirements to ISO/IEC 17025 that were used during the accreditation process. In 2016, ASCLD/LAB merged with ANAB who now takes on that role in addition to many others. ANAB provides accreditation for ISO/IEC 17025 testing and calibration laboratories and forensic testing agencies, ISO/IEC 17020 inspection bodies and forensic inspection agencies, ISO Guide 34 reference material producers, ISO/IEC 17043 proficiency test providers, ISO 15189 medical test laboratories, ISO/IEC 17021 management systems certification bodies, and industry-specific programs”. Source: https://www.theauditoronline.com/anab-merge-forensics-operations-ascldlab/ (Links to an external site.) (https://urldefense.proofpoint.com/v2/url?u=https-3A__www.theauditoronline.com_anab-2Dmerge-2Dforensics2Doperations-2Dascldlab_&d=DwMFaQ&c=sJ6xIWYxzLMB3EPkvcnVg&r=hwQOb3wMBXNUOwhsoHWkyK_KoXRE7_KuulfcDaUKV8I&m=39c7fbtA7CnQpZtia-ennliyDef8PYMl69J0WSS4wmyKBmOrfQBiWYsP148BITn&s=WbKTkdVveqn9aONA9wBXkm79BXGmximfTAiBVlIapWA& Please go to the following websites for more information about the merger and information about accreditation services through ANAB https://anab.ansi.org/latest-news/anab-and-ascldlab-merge-operations (Links to an external site.) (https://urldefense.proofpoint.com/v2/url?u=https-3A__anab.ansi.org_latest-2Dnews_anab-2Dand-2Dascldlab2Dmerge-2Doperations&d=DwMFaQ&c=sJ6xIWYxzLMB3EPkvcnVg&r=hwQOb3wMBXNUOwhsoHWkyK_KoXRE7_KuulfcDaUKV8I&m=39c7fbtA7CnQpZtia-ennliyDef8PYMl69J0WSS4wmyKBmOrfQBiWYsP148BITn&s=bEb8vxK7kcBImgtD9IgE0OWtEWmDm8IdiTmk9sjt98&e=) https://anab.ansi.org/en/forensic-accreditation (Links to an external site.) (https://urldefense.proofpoint.com/v2/url?u=https-3A__anab.ansi.org_en_forensic2Daccreditation&d=DwMFaQ&c=sJ6xIWYxzLMB3EPkvcnVg&r=hwQOb3wMBXNUOwhsoHWkyK_KoXRE7_KuulfcDaUKV8I&m=39c7fbtA7CnQpZtia-ennliyDef8PYMl69J0WSS4wmyKBmOrfQBiWYsP148BITn&s=5EjH7MJ9pX6Myr4TKBKYzRl1BU255iN8eGv7VSa6CbA&e= ANAB also provides supplemental accreditation requirements that forensic and calibration laboratories must comply with. ANAB’s AR 3125 ISO/IEC 17025:2017 – Forensic Testing and Calibration Laboratories Accreditation Requirements, can be found here: https://anab.qualtraxcloud.com/ShowDocument.aspx?ID=12371 (Links to an external site.) (https://urldefense.proofpoint.com/v2/url?u=https-3A__anab.qualtraxcloud.com_ShowDocument.aspx-3FID3D12371&d=DwMFaQ&c=sJ6xIWYxzLMB3EPkvcnVg&r=hwQOb3wMBXNUOwhsoHWkyK_KoXRE7_KuulfcDaUKV8I&m=39c7fbtA7CnQpZtia-ennliyDef8PYMl69J0WSS4wmyKBmOrfQBiWYsP148BITn&s=JwpQKAzYjxsWnptmvhvqYpuX_xlsHqYZXXzhFjClUk&e=) See also https://www.justice.gov/archives/ncfs/file/839701/download (https://www.justice.gov/archives/ncfs/file/839701/download) Module 2: Crime Scene Investigation Module Overview Page 1 Introduction Arguably the most important aspect of forensic examination occurs at the crime scene. If important evidence is missed, contaminated or destroyed, the outcome of the whole case may be jeopardized. Consequently a great deal of effort has been put into the development of an array of techniques and technology to aid crime scene investigation. The use of computer databases, automated comparison systems and DNA profiling methods has greatly improved law enforcements ability to solve a crime. The development of more robust, sensitive, and portable analytical and processing equipment continues to add to capabilities of crime scene investigators. Crime scene investigation is also facilitated through increased collaborations with scientists from many scientific sub-disciplines and specialties. Objectives At the end of this course the student will understand the principles of crime scene investigation including: Preserving the crime scene Recording the crime scene Searching the scene Collection and packaging of evidence Crime scene safety Module 2: Crime Scene Investigation Page 2 Crime Scene Environment Crime Scene Environment In the management and processing of physical evidence Crime Scene Investigators interact with: Other police officers (including general duties, investigative, specialist and administrative areas) The judicial system including; legal practitioner, (prosecution and defense lawyers) judges and courts (including civil, coronial, criminal and appeal Courts) Forensic scientists (including specialist laboratories and experts) Forensic medical practicioners (including pathologists, psychologists and psychiatrists) General community often represented through juries, including those involved in specific incidents (victims, suspects, witnesses) and expectations shaped by media reporting of actual cases, fictional material, (books, magazines, television and movies). A professional crime scene investigator will be sensitive to the needs of all the above players. Teamwork in criminal/coronial investigations is essential. Crime scene investigators conduct the initial examination of the scene to ensure that all physical evidence is collected and processed. Beyond the scene, further evidence may become available (e.g. from the offender). The coordination of how this evidence is collected, processed and presented to Court will have important scientific and legal implications. Role of the Crime Scene Investigator One of the most important aspects of the crime scene investigator’s role is to establish clear and direct lines of communication with forensic experts, investigators etc. This communication begins from initial notification of the crime or incident, attending the scene, through the various phases of the investigation, to the final presentation of evidence at Court and (any subsequent appeal). Crime scene investigators perform the technical aspects of collecting, recording, examining, and analyzing physical evidence as an integral part of the investigating team. Crime scene investigators should be effective managers: At the scene of the crime or incident Of the processing of physical evidence collected from the scene Of the investigative process as it relates to physical evidence Of the final presentation of physical evidence at court Crime scene investigators should work closely with the investigating police officers by providing them with all the relevant details about the processing of physical evidence. Module 2: Crime Scene Investigation Page 3 Principles of Crime Scene Investigation - Securing the Scene Principles of Crime Scene Investigation - Securing the Scene Some of the most important aspects of crime scene investigation include: Securing and protecting the scene Prevention of contamination Preservation of physical evidence Securing the Scene Personnel responding to a crime scene must approach and enter the scene cautiously while being aware of the presence of personnel, vehicles, ongoing events, any potential evidence, and the environmental conditions. They should be aware of the possibility of secondary, or multiple crime scenes, and any initial observations such as the presence of distinctive odors, sounds, etc. At this time, the investigator should assess the site and give consideration to any safety and personal protective equipment measures that need to be taken to protect themselves and other personnel. On initial entry into the scene, the crime scene investigator should proceed with great caution, keeping in mind the potential to destroy evidence at the scene. A plan should be formulated to minimize destruction of evidence by considering the initial physical approach. In particular the following should be considered: Use an entry other than that taken by the suspect Establish the path taken by other persons first on the scene Consider the loss of trace evidence on entry throughout your examination, (e.g.. shoe/foot impressions on the floor) Reassess Occupational Safety and Health (OSHA) issues Establish the extent of the scene and additional assistance that may be required Establish an entry and exit path for the Senior Investigating Officer and specialists to access the scene, if necessary The first responsibility of the initial responding officer is to secure and protect the scene. Securing the scene is completed by setting up physical barriers to prevent unwanted persons from entering the perimeter. Officers then protect the scene by physical presence at established points outside of the inner perimeter. It is their job to identify everyone present at the crime scene, and take steps to prevent the alteration or destruction of physical evidence, by restricting movement, location and activity. Establishing, defining, and controlling boundaries to the scene achieve this. These boundaries are often influenced by the location and the type of crime committed. Boundaries usually start at the focal point of the scene and extend outward to include: Where the crime occurred Potential points of entry and exit of suspects and witnesses Places where the victim or evidence may have been moved These boundaries are critical in controlling the integrity of evidentiary material, and are achieved by setting up physical barriers, controlling the flow of personnel into and out of the scene, documenting the entry of persons entering or leaving the scene, and taking measures to prevent the loss, or compromise of evidence from weather, footsteps, and tire tracks. Module 2: Crime Scene Investigation Page 4 Principles of Crime Scene Investigation - Processing the Scene Processing the Scene The first step in routine crime scene investigation is establishing a plan of action and crime scene reporting protocol. This involves listing the objective of each process or step of the scene process and assigning tasks to each work objective. The basic protocol for scene processing can be summarized as several sequenced tasks: Surveying the crime scene Photographing and searching the crime scene Mapping and measuring the crime scene Recording and documenting the location of physical evidence at the crime scene Searching for fingerprints and other physical evidence To obtain the most useful evidence, the investigator must approach each crime scene in an organized and routine manner. By conducting carefully executed searches; following routine processing protocols and operating procedures the investigator will facilitate the preservation of fragile evidence and obtain the most useful evidence present. Module 2: Crime Scene Investigation Page 5 Principles of Crime Scene Investigation - Recording the Scene Recording the Scene All activities conducted at the scene, and all observations made, must be documented as soon as possible to preserve the events and information. Documentation may take the form of sketches, written notes, photography and video. A well-documented scene ensures the integrity of the investigation and provides a permanent record for later evaluation. Documentation must be made of any observations of the crime scene, including the location of persons, vehicles, or items within the scene, and the condition and appearance of the scene upon arrival. Most records are made during the scene walk-through. The investigator in charge and any personnel responsible for processing the scene conducts this. During the walk-through, a walkway other than the established path of entry should be used to reduce contamination. Crime scene documentation may be conducted on preprinted documents or forms designed for recording certain aspects of crime scene investigation. Many of these documents have been developed and refined from years of actual case experiences. The design of the document may vary, but the purpose and goals behind their use are usually identical from one agency to another. These documents may include body outlines for recording injuries, clothing outlines for recording damage or staining, and data analyses sheets for the simple recording, reference to, and interpretation of basic laboratory and presumptive tests. There are normally six important categories of documentation that are considered applicable to any search: Administrative Worksheet Narrative Description Photographic Log Diagram/Sketch Evidence Recovery Log Latent Print Lift Log Identiﬁcation, Collection and Preservation of Evidence During the walk-through, fragile and perishable evidence should be identified and protected. Such evidence should then be documented, photographed and collected. During processing of a crime scene, contamination is controlled by limiting access to those directly involved in scene processing; designating specific areas for trash and equipment, and using singleuse materials for the collection of biological materials and other trace evidence. Initial Scene Notes Crime scene investigator’s notes should be well organized. An effective way to organize notes is to take and record them chronologically. Official notes should be made first outlining: Basic facts such as times, dates, names, location, victims, suspects etc Brief notes about the scene Conversations, receipt of property etc Detailed Examination When making a detailed examination of the scene one method is to use lined notepad. If you use this method it is good practice to number the pages as they are used. Headings should be used as much as possible to assist in organizing the notes. New computerized systems of documentation exist and can be used for notes, sketches, photos and lists. iPads™, Windows-based tablets and Apps are now available to assist investigators with the continuous influx of information and to help keep files organized. It is important to remember to keep items clean between uses and to download all information to a secure central server to preserve the chain of custody. Accuracy Written notes should be detailed and specific. It is imperative that the time is recorded for specific events or items uncovered during the examination. E.g.“3.05pm: Examined locking mechanism to rear door of premises, Whitlock double deadlock mortise type. Forcing to inner section of doorjamb 5 cm below lock. The operation of the locking switch was extremely tight and appeared to have been damaged during the forcing. Red paint recovered from the locking catch.” Dictaphone A Dictaphone can be useful for recording complex and large scenes. The obvious advantage of a Dictaphone is the speed with which notes can be taken. However, there are also disadvantages, e.g. The user does not have facility to check the notes readily at the scene and unless transcribed immediately details cannot be given to investigators. Well-organized notes taken in a logical sequence should assist the investigator to organize the processing of the scene. The notes can operate as a checklist to ensure all possible examinations and searches have been made and that the scene has been recorded properly. Measuring/Sketching a Crime Scene Measuring a crime scene and preparing accurate scale or sketch plans can be of great assistance in a criminal investigation. Your organization may or may not require you to measure and prepare scale plans for a crime scene. In any case, one of the most practical and helpful ways of taking crime scene notes is to sketch the scene and you should endeavor to develop skills that will allow you to prepare sketches of scenes Maintaining the skill to hand-draw a scene using rulers, templates and graph paper is important, however many proprietary computer-aided design (CAD) programs exist and work in conjunction with laser mapping systems, 360° scanners and other mapping devices to create scale drawings. The days of hand-drawn sketches are coming to a close with the availability of new technology, which saves time and energy and improves accuracy. With minimal training hours and ease of use, these new tools make diagramming a scene both precise and fast. See the following for examples: http://psg.leica-geosystems.us/page/applications/crime-scene-investigation/ (http://psg.leica- geosystems.us/page/applications/crime-scene-investigation/) http://www.sun-sentinel.com/local/broward/fl-miramar-police-panoscan-crime-scene-20140318story.html (http://www.sun-sentinel.com/local/broward/fl-miramar-police-panoscan-crime-scene-20140318story.html) Module 2: Crime Scene Investigation Approach to Searching Page 6 Approach to Searching The search is one of the most important tasks a crime scene investigator will undertake at the crime or incident scene. A complete and systematic search must take place in order to locate all relevant physical evidence, which is subsequently recorded, collected, examined and presented to the court. When searching a crime or incident scene, the crime scene investigator should consider the nature of physical evidence and the principles of exchange and transfer. This raises the question of what are we looking for? One crime scene investigator recollects a question posed by a police offcier at a murder scene who asked, “Can I help? Tell me what you are looking for?” The crime scene investigator responded, “I don’t know exactly what I am looking for, but I will know when I find it.” This was an accurate response regarding scene searching. This is a problem that a crime scene investigator will constantly confront. Each crime or incident scene will be unique and must be approached with an open mind. The known facts will only assist in providing what is likely to be found. Only a thorough and systematic search will determine what is to be found. Case Study An elderly woman was murdered in her home and found by family members after attempts to contact her failed. The victim was located in the bedroom on the floor with evidence of blunt force trauma to the head. A tooth was found on the bedspread of the neatly-made bed. A search of the residence by crime scene investigators revealed a piece of half-eaten cantaloupe on the kitchen counter. The fruit was fresh. A swab was taken and immediately submitted to the laboratory for DNA analysis and compared to a buccal swab from a person of interest. The DNA from the cantaloupe matched the DNA of the lawn maintenance man. The suspect was arrested and questioned, but denied any involvement. Subsequent investigation revealed that the suspect had pawned some of the victim’s jewelry and a bloody shirt was found at his residence upon service of a search warrant. The suspect was found guilty of capital murder and is currently on death row. The collection of evidence should always be prioritized to minimize loss and contamination. Usually a secure area for the temporary storage of evidence in accordance with rules of evidence and chain of custody is established. A systematic search pattern is selected for the collection of evidence; this is usually influenced by the size and nature of the scene. Several patterns of searching are routinely used depending on the nature of the crime scene being processed. When processing the scene, the scientist should select a progression of processing and collection methods so that initial techniques do not compromise subsequent processing or collection methods. The most transient evidence should always be collected first, progressing to the least transient evidence, moving from the least intrusive collection techniques (e.g. oblique lighting, ALS) to the most intrusive techniques (e.g. chemical processes). It is always best to bring the container to the evidence, not the evidence to the container. The handling of physical evidence is one of the most important factors of an investigation. The collection of evidence must be documented, by recording its location at the scene, the date of collection and who collected it. For each item collected a chain of custody must be established. Care should also be taken to acquire appropriate reference and standard materials from the scene for comparison needs. A final scene walkthrough can ensure that all evidence has been collected and that materials are not inadvertently left behind The handling of physical evidence is one of the most important factors of an investigation. The collection of evidence must be documented, by recording its location at the scene, the date of collection and who collected it. For each item collected a chain of custody must be established. Care should also be taken to acquire appropriate reference and standard materials from the scene for comparison needs. A final scene walkthrough can ensure that all evidence has been collected and that materials are not inadvertently left behind. When conducting an investigation, always complete processes in the same way using sterile equipment, gloves and appropriate PPE. When questioned during deposition or in court, there will be no dispute as to what procedures were followed. Go to http://www.crime-scene-investigator.net/collect.html investigator.net/collect.html) for a detailed list of evidence collection guidelines for: Bloodstains Seminal stains Hair Fibers Glass (http://www.crime-scene- Paint Flammable liquids Firearms evidence Tool marks Controlled substances and medicinal preparations Questioned documents Latent fingerprints Module 2: Crime Scene Investigation Page 7 Approach to Searching Continued Approach to Searching - Continued The principle of trace evidence and exchange forms the basis to crime scene examination. There are three methods to adopt in your approach to searching. 1. Positive Search “There is nothing like first-hand evidence.” (Doyle, 1947) This approach to searching is to find evidence at a crime or incident scene that will provide physical evidence about the case under investigation. E.g. murder weapon, relevant blood stained clothing or trace evidence - this is, a positive search. 2. Negative Search “One should always look for a possible alternative and provide against it. It is the first rule of criminal investigation.” (Doyle, 1947) This approach to searching is to determine that something was not there. E.g. the absence of a forced entry at a murder scene could indicate that the victim may have known the offender. The absence of skid marks at the rear wheels of a vehicle, involved in a collision may indicate a lack of action or inattention by the vehicle driver to stop the vehicle prior to impact. 3. Information/Intelligence “If I had not taken things for granted, if I had examined everything with the care which I would have shown had we approached the case de novo and had no cut-and-dried story to warp my mind, would I not then have found something more definite to go upon?” (Doyle, 1947) The search is partly dependant on information, both verbal and visual, of the known circumstances of the incident. However, logic, reason, intuition and an open mind will assist in the process of searching. The crime scene investigator should look at a variety of possible explanations of the known facts and use intelligent thought and concentration to further assess the correctness of the information received. The crime scene investigator is constantly assessing and reassessing what might be found. A crime scene investigator who attended the scene of a break and enter proved an example of this application. The investigating officer told the crime scene investigator that a likely suspect had been arrested. The investigating officer indicated that the offender had cut through and removed the staple section of a sliding bolt thus disabling the padlock, which secured the front door to the premises. The senior investigating officer indicated that a pair of pliers had been found on the suspect and it was likely that a tool mark comparison could be made of the pliers and the cut staple. The crime scene investigator attended the scene, examined the cut staple and took the usual notes, photographs etc. The pliers had not been viewed by the crime scene investigator at this stage. It seemed that the only evidence available would be a comparison analysis of the tool mark and pliers (which is not always conclusive). However, a thorough search of the floor indicated a far more convincing and positive item of evidence, a small broken fragment of metal. The fragment of metal was collected. Later that day the crime scene investigator was handed the pair of pliers that were found on the suspect. The pliers were examined closely and the tip of one of the jaws was missing. The metal fragment collected from the scene was found to be the tip of the missing jaw. This simple example shows many aspects to crime scene searching which need to be understood and applied at every crime scene: The positive search which centers on known facts to locate evidence which is expected to be found (the tool mark in the above example) The negative search, which centers on known facts to indicate that no evidence, was found to indicate an alternate explanation (e.g. could the suspect have entered through another door) The intelligent search which requires a combination of known facts, consideration for other explanations and a systematic and thorough approach to locate any other evidence (finding of the tip of the pliers, based on information about a pair of pliers) Searching Technology There is a wide range of technology that can be used in scene searching (e.g. light sources, polilight, UV light, dust mark lifting device, screens and sieves, rakes and spades, metal detectors, gas sniffers etc.) Other groups within your police service and external agencies may be able to provide other resources. Searching Methods An investigator should develop a plan or method appropriate to the type of scene. There are five basic methods that are universally accepted. These are: 1. Strip method 2. Spiral method 3. Wheel method 4. Grid method 5. Zone method The area(s) to be searched will often be determined by the: Nature of the incident Nature of the physical evidence present Location Terrain Lighting conditions Size of the area to be searched Established facts Organizing Large Searches When extra police officers are needed to search a large scene, a team briefing should be held. The briefing should be organized with the senior investigating officer and should provide: An overview of the relevant facts Details of any specific evidence, which is being searched for The search plan to be adopted i.e. search areas and personnel The manner in which the searchers should search the scene and what is required of them (e.g. on hands and knees) The time frame over which search is to be conducted Procedure to be followed when evidence is located i.e. preservation till it can be recorded in situ The Golden Rules of Searching When scenes or items are searched (either large or small) there are three golden rules that should be applied to maximize the recovery of evidence. 1. Search areas should be determined to maximize concentration. Each area should take no more than 20-40 minutes to search. 2. Breaks should be taken after each search. (At least 10 minutes) 3. Search the same area twice so that nothing is overlooked. Further reading: see basic equipment for crime scene investigators at http://www.feinc.net/equipmt.htm (http://www.feinc.net/equipmt.htm) and https://www.fbi.gov/file-repository/handbook-of-forensic-services-pdf.pdf/view (https://www.fbi.gov/file-repository/handbook-of-forensic-services-pdf.pdf/view) for protocols on Crime Scene Search, Recording, and Physical Evidence Collection. A more detailed description of organization and procedures for crime scene processing can be found at http://www.feinc.net/cs-proc.htm (http://www.feinc.net/cs-proc.htm) step-by-step guidelines for crime scene processing. Case Study. This site provides concise A teenage victim contacted police after being sexually assaulted at gunpoint at a bus stop in the early morning hours. Crime scene investigators were summoned to the scene and began a search of the area for evidence of the assault. The search area encompassed the bus stop area sidewalk and a large wooded area adjacent. The wooded area was covered with pine straw and leaves and no definitive information was known as to how far into the woods the suspect had forced the victim. A methodical search of the area yielded nothing of evidentiary value. The victim agreed to return to the scene to assist investigators. The victim recognized some of the vegetation and gave investigators a starting point for another search. Careful examination of the leaf litter revealed liquid biological evidence, which was collected and immediately sent for DNA analysis. A CODIS hit was returned for a registered sex offender who resided in the area. When searched incident to arrest, he still had possession of the gun described by the victim as well as the victim’s cell phone, upon which he had video recorded the entire crime. He was sentenced to life in prison. Module 2: Crime Scene Investigation Page 8 Legal Considerations of Crime Scene Investigation Legal Considerations of Crime Scene Investigation To avoid the exclusion of evidence in court, due to illegal search and seizure practices, the removal of any evidence from a crime scene must conform to Fourth Amendment privileges. In order to protect the rights of the people there must be probable cause before a specifically described site can be searched and items of evidence seized, under the authorization of a court issued search warrant. There are a number of defined circumstances where the police can search for evidence in the absence of a search warrant: Emergency circumstances In the prevention of loss or destruction of evidence A search of a person and property in immediate control of the person as long as it is in the event of a lawful arrest A search made under consent of the party involved In all other situations a search warrant must be issued, before investigating and retrieving physical evidence from a crime scene. Module 2: Crime Scene Investigation Page 9 Examinations: Purpose and Types Of Purpose of the Examination The purpose of an examination is to: Locate and identify potential evidence Provide information about the crime or incident Assist in the corroboration or otherwise of information provided by suspects, victims or witnesses Types of Examinations The type and scale of examination to be carried out will be determined by the: Seriousness of the offence/incident, type of the offence/incident and relevant circumstances The nature of the scene Before examining evidence, which involves moving, or disturbing it, the following should be checked: Have appropriate OSHA requirements been followed (e.g. bio hazards procedures) Has the area or item to be examined been photographed? Are there adequate notes, sketches and measurements of the area or item? If the area or item is to be moved or disturbed during the examination, will evidence be contaminated or destroyed? When anything is moved or disturbed during the examination, consider that other evidence might be present. Always examine the entire item on all surfaces and check the area from where the item was moved, particularly for the presence of trace evidence. Special consideration should be given to trace evidence still attached to an item. If it is considered that trace evidence may be lost or destroyed during handling or examination, it should be removed from the item and packaged separately. It is preferable to collect items in their entirety and carry out further examinations as required under controlled conditions. Module 2: Crime Scene Investigation Page 10 Approach to Scene Examination Approach to Scene Examination There are three essential requirements in your approach to scene examination: 1. Organization 2. Thoroughness 3. Cautiousness An organized approach considers the need for other experts. E.g. A coordinated search with fingerprint experts, photography and video, prior to disturbing any items, the forensic pathologist to view the body in position before it is disturbed, and so on. A thorough approach will involve consideration of all the facts. Full details of the examination should be recorded at the time. It is vital that you have comprehensive and thorough notes, as these will support your ability to prepare statements and to present your evidence at Court. Remember, if it is not documented, it didn’t happen! A cautious approach involves considering alternative theories for what might have happened during the incident. Think through the incident and reconstruct the actions of those involved. It may be necessary to review possible scenarios on several occasions e.g. “Could it have been done this way or that way, or is that not feasible?” You will constantly be re-evaluating the evidence and attempting to disprove or refute the null hypothesis; that is to prove that a relationship between persons, items and scenes is possible. What Evidence Should be Examined? Where details of the incident are sketchy, it is never wise to underestimate the importance of an item. Be curious of every item and never overlook anything. As more details come to hand, it is easier to eliminate these from the investigation, than to have lost that evidence forever. Liaison with the senior investigating officer is vital throughout the process of evaluating the relevancy of the physical evidence. At times it may be better to collect too much than to overlook something important. Examination starts at the scene, however many items will require further examination under controlled conditions. Detailed records (written, sketched, photographic) should be maintained of all examinations and your findings. Case Study The homicide of a female victim took place in a small residence and preliminary findings revealed a paring knife under the victim’s body. While awaiting lab results from the knife and other evidentiary items found near the victim, crime scene investigators searched the other areas of the residence. In the bookcase in the living room, an investigator noticed two silver beer cans behind some law books. The cans were collected and processed for DNA and latent prints. AFIS search results showed one fingerprint that was found to match a person of interest. A search warrant of his residence revealed several items belonging to the victim and a bloodstained shirt in the washing machine. The suspect was found guilty of first-degree murder and was also tied to another attempted murder and robbery, in which he was also found guilty. Examining a Break In - The Basis of Most Crime Scenes One of the most common crimes is that of break, enter and steal. Understanding how to examine this type of scene properly is essential. In many instances a break in (or scene made to look as if a break and enter took place) may be part of a more serious crime e.g. murder, sexual assault, arson. By practicing proper techniques and following protocols at less complicated crime scenes, your skills will be fine-tuned when the call comes in for a complicated or multi-scene investigation. Module 2: Crime Scene Investigation Collection of Evidence Page 11 Collection of Evidence It is important to prioritize the collection of evidence to prevent loss of, or damage to, an item. Smaller items or evidence are usually prone to damage. Generally: Ensure fragile and/or transient evidence is collected first e.g. latent fingerprints Then collect trace evidence e.g. blood and fiber Finally, collect larger items Cross Contamination and Biological Degradation A major consideration in the handling and management of physical evidence is the possibility of cross contamination and/or biological degradation. When collecting an item from the scene care must be taken to ensure that it is collected in a way, which will preserve (as closely as possible) its original condition. Adopting the appropriate packaging procedure and OSHA guidelines can minimize contamination. The wearing of gloves, disposable shoe covers and body suit will reduce the possibility of cross contamination from your clothing. Although these suits shed white cellulose fibers, these fibers can be easily identified and eliminated. All equipment and packaging materials should be kept in a clean condition to avoid contamination. When performing collection of samples, always use sterile or single-use instruments. When completing latent print processing, using new brushes, new powders and fresh chemicals is essential for each area being processed. Contaminants can be transferred from item to item or surface to surface, so using clean tools and reagents is imperative should the need for DNA analysis of any recovered prints not suitable for comparison arise. Keeping in mind the possibilities of future analysis will ensure the best processes and techniques when on the scene. Packaging There are a number of general procedures to be followed for the collection and packaging of items: All items must be packaged separately to avoid cross contamination Each package must be sealed to avoid external contamination or loss of evidence Each item should be packaged in the appropriate type of packaging to prevent biological degradation e.g. Bloodstained items in paper bags. If the item is removed from the original packaging for any reason, the original packaging material should be kept and care taken to preserve the integrity of the item. Labeling At the time of collection of an item, a detailed label should be attached to the package. Details on the label may include some or all of the following: Time and date collected By whom collected Type of incident Description of the item Location of the incident Suspect and victims name Location of the item Name of the Senior Investigating Officer and their location Crime scene investigators name and the job number Labeling identifies the item, assists with proving continuity and ultimately admittance into evidence at court. Your organization will have standard procedures for labeling items. Module 2: Crime Scene Investigation Continuity and Records Page 12 Continuity and Records Continuity refers to the chain of custody of an item, from initial location, collection and any subsequent movements of that item, through to admission into evidence at court. Continuity is maintained by: Accurate records (of the scene and item) Detailed labeling, appropriate and sealed packaging Accurate official records and logs Secure storage of the item(s) Restricted movement of the item(s) Full documentation of any subsequent movement It is preferable that the crime scene investigator is the only link in the chain of custody of an item. Where this is not possible, movement and handling of the item should be fully documented and kept to a minimum Understanding Trace Evidence Trace evidence is easily contaminated if it is not collected or preserved properly. This topic will be covered in a separate module. Module 2: Crime Scene Investigation Page 13 Interpretation and Limitations Interpretation With all aspects of searching, examining and collection undertaken, the most important aspects still remain, those of assessment and presentation of evidence. Assessment involves laying out all the known facts and piecing these together to reconstruct the events relative to the located physical evidence. Interpretation of a crime or incident scene may: Assist in establishing how the incident occurred Prove or disprove witness, suspect or victims, versions of the incident Provide investigators with information, which may assist with inquiries and interviewing of witnesses, victims, and suspects If suitable be used as evidence at court Interpretation may suggest a theory of what occurred, based on: Observations at the crime or incident scene The physical evidence located Information received from the Senior Investigating Officer e.g. interviews and subsequent inquiries Results of examinations, analyses and other specialized tests Interpretation commences on your arrival at the crime or incident scene where you make an assessment based on the known facts and the physical evidence present. Interpretation is a way of thinking which focuses on the possible types of evidence which you might expect to find. It should not limit the examination but serve to enhance it. It is important to continually reassess your interpretation theory(s) as you process the scene (i.e. there may be several possible alternatives). Once the results of all the tests (e.g. physical comparison, experimental burn, blood groupings etc) are available then the crime scene investigator can formulate one or more interpretations of the scene from all available information. The crime scene investigator should seek to review the evidence including photographs, plans and notes with experienced crime scene investigators and/or external experts who may contribute their assessment and interpretation of the scene. Limitations Interpretation can be likened to a jigsaw puzzle, a matter of assembling the pieces together. However, it becomes difficult or not always possible when pieces are missing or do not belong. There are four basic limitations to the process of reconstructing the incident: 1. Quantity and quality of the information received, physical evidence present and method of recording. a. Facts may: Speak for themselves Require only the slightest inference Be scarce Be unreliable and therefore make interpretation difficult, inaccurate or poor recording of the crime or incident scene can render interpretation impossible 2. Ability and expertise of the crime scene investigator. Given the same information, one person may form a more reliable and accurate conclusion or opinion, based on: a. Aptitude for recognizing relevant and expected signs at the crime or incident scene e.g. post mortem lividity to determine if body has been moved, marks on the roadway in a vehicle collision b. Working knowledge of the basic sciences e.g. physics, chemistry, mathematics c. Ability to distinguish between fact and opinion in your own thoughts and from information obtained from other persons 3. Extent of interpretation required. Interpretation does not generally involve a total description of what occurred, but tends to be more specific in its purpose. Interpretation often defines the questions in contention and seeks to find possible answers. (e.g. the speed of a vehicle and position of the vehicles at the time of impact, in a vehicle collision.) 4. Time and financial resources available. Particularly in seeking expert opinions. The crime scene investigator should assess the likely worth or weight of expert opinions to the circumstances of the investigation. This should be discussed with the Senior Investigating Officer. Results The results of interpretation are the formation of opinions or likely conclusions. The acceptance of which is dependent on: The information, which the interpretation is based on The integrity of the physical evidence Who makes the conclusion? The circumstances of the incident Interpretation must be thorough and a reliable report made of the observations, rather than the investigator's belief of what occurred. This is largely reliant on the peer-review process discussed earlier. Others will closely scrutinize the evidence you present, especially the counsel for the accused in court. Module 2: Crime Scene Investigation Types of Evidence Page 14 Human Remains and Identiﬁcation Many crime scenes are the starting points of homicide investigations. An investigator’s responsibility is to help establish the manner of death (accidental, homicide, suicide or natural causes) while preserving any evidence present at the scene. At a homicide scene, moving the body, clothing or any other items covering the corpse can easily result in the loss of evidence. Note taking is a particularly important part of crime scene investigation. Such notes should include: Position of the body Description and state of clothing (is it partially removed, stained, tangled or twisted?) Describe the location, intensity, size, and direction of flow of any staining if possible. Type of stain (blood-like, semen, dirt, vomit, feces, urine or some other fluid) Any visible damage to the clothing and body Description of bloodstains (spots, spatter or smearing and directionality) Appearance of evidence removal (has the body been washed or blood cleaned from the body?) Estimated amounts of blood (has staining penetrated layers, carpeting or other surfaces, is it superficial?) Livor, rigor and algor mortis (are they present and consistent with the body position and given timeline, if known?) Decomposition, mummification, saponification, if present Special consideration must be given if the corpse is located outdoors, or has apparently been moved from another location crime scene. The remains may be partially decomposed or damaged by insects or animals. The important points of processing human remains are stressed in an article that can be seen online at http://www.crime-scene-investigator.net/corpse.html (http://www.crime-scene- investigator.net/corpse.html). This paper stresses the need for careful examination and application of standard procedures for maximum crime scene and evidence protection and outlines the different types of evidence that may be encountered and include the appropriate techniques for the collection of Trace Evidence, Body Fluids and Latent prints Recovery of Human Remains The recovery of human remains comes with a number of associated difficulties as often the body has undergone decomposition and alteration. There may be some skeletal parts and some organs remaining, which together with clothing fragments may provide useful evidence. Human remains are found in a variety of places; often outdoors, but also indoor, in attics, furnaces and basements. A body may have been buried in soil, frozen, covered with brush or overgrown vegetation. With outdoor remains, clothing and evidence may be spread over a wide area and have been subjected to animal interference and insect infestation. With appropriate care and procedures, all of these scenarios can still provide large amounts of evidence. Read the article at http://www.feinc.net/cs-recov.htm (http://www.feinc.net/cs-recov.htm) , which provides a simplified investigation protocol and common sense approach to obtaining evidence from recovered human remains. One of the newer methods used to recover the remains of buried bodies is the use of police detector dogs. In the same way dogs can be trained to locate drug substances, dogs are being trained to locate decomposing bodies. See the article on cadaver dogs at: http://www.crime-scene-investigator.net/cadaverdogs.html (http://www.crime-scene- investigator.net/cadaverdogs.html) Forensic Anthropology Identification of a victim from recovered remains may require the help of different scientific disciplines to aid in the identification process. Forensic anthropology is the scientific discipline mainly concerned with the study of bodily or skeletal remains. Over recent years, scientists from this field have constructed a number of databases, cataloguing gender and racial differences in the physical structure of bodies. Forensic anthropologists, are familiar with human anatomy, and can often identify the sex, age, or ancestry of human remains found at crime scenes or uncovered by excavations. Its possible to determine two types of information from remains: Physical characteristics such as sex, ethnicity, approximate age, stature, certain disease states and old injuries The actual identification of the individual Anthropologists can obtain information from teeth that may determine the approximate age of the victim. The cranium and the ossification lines, or sutures, of the cranium provide information on gender and approximate age. Approximate height can be determined from the skeleton and the longer bones of the limbs. Hair resists changes very well, if it hasn’t been exposed to fire and may still be found at the scene even when the body has undergone severe changes and decomposition. This may be used to determine the hair color of an individual. Forensic Odontology The field of forensic odontology uses dental records to help in human identification, and is often necessary for the identification of unrecognizable bodies, after fires or mass disasters, and in the identification and comparison of bite marks. Pre-death information contained in dental records and post mortem notes, information and features need to be obtained, documented and compared as part of the identification process. See the American Board of Forensic Odontologists website at http://www.abfo.org/ (http://www.abfo.org/) mass disaster identification. for more information on bite mark examination and 5 Module 2: Crime Scene Investigation Page 15 Estimating Time of Death Estimating Time of Death In murder, accident, and suicide cases, establishing the time of death is important for the investigation. This can be done in a number of ways using post mortem changes. Important factors include: Changes in the eyes (dulling of the cornea and the appearance of a film) Body temperature cooling that can be related to the outdoor conditions ; temperature of the body at the time of death; whether the body is clothed or unclothed. A body usually reaches ambient temperature 18 to 20 hours after death Rigidity that appears 6 to 12 hours after death ( rigor mortis). The flaccid corpse begins to become rigid due to biochemical changes in the muscle tissue; the degree and extent of rigidity can be used to estimate time of death. Rigidity remains for 2 to 3 days then disappears again When blood circulation stops, blood pools in the lower extremities of the body due to the effects of gravity, causing a purplish red appearance ( liver mortis). Lividity first appears 1 hour after death with full appearance in 3 to 4 hours. Lividity can also be used to determine whether a body has been moved from its original position Decomposition or putrefaction is the breakdown of the body due to autolysis and bacterial decomposition. These events convert tissues of the body into liquids and gases causing discoloration, bloating, and swelling. Fluid filled blisters appear on the skin, and stomach contents may be forced out of the mouth, nose and anus. Submersion in water causes similar effects but the processes are generally slowed due to colder temperatures. Soil organisms also decompose bodies buried in soil. In one to 3 years all the soft tissue will have disappeared leaving only bones. Bodies may be preserved by mummification or through the formation of adipocere, a waxy covering which begins to develop in 6 to 8 weeks as body fats are hydrolyzed. Insect Infestation and Forensic Entomology Most corpses are susceptible to insect infestation. The types of insects and insect fragments present on a corpse or remains can be used to estimate the time of death by analysis of the insect life cycles. The following web site provides a comprehensive description of the events that happen after death, common insects of infestation, and how they can be used to determine the time of death: http://www.forensic-entomology.com/ (http://www.forensic-entomology.com/) http://www.forensicentomologist.org/ (http://www.forensicentomologist.org/) and Module 2: Crime Scene Investigation Page 16 Crime Scene Photography Crime Scene Photography Crime scene photographs are permanent and comprehensive pieces of evidence that may be presented in court to prove or disprove facts in question. Although an investigator can verbally describe the crime scene, photographs are able to present the same facts in a more accurate and easily understood way. Crime scene sketches made to scale from a rough sketch that is made at the scene normally accompany crime scene photographs. Later, a properly scaled schematic drawing is made to give precise measurements, compass directions etc. Always remember the purpose when taking photographs. This will help you decide what to do and in what order. For example, at a scene there are three things to record: 1. The overview, a general shot with features to identify the location 2. The location of any significant evidence, usually a mid-range shot 3. The evidence detail, perhaps with close-up procedures If you are photographing injuries, then you must use color film and should be aware that injuries will change in appearance with time. Crime scene photographs must be a fair and accurate depiction of the scene and evidence. A measuring device, such as an AFBO scale, must be used when depicting the relative size of an item. Examination quality photographs should be taken of fingerprints, toolmarks and any other items that require forensic comparison. This allows the analyst to properly scale the photograph in comparison to the known item. Digital cameras allow for immediate feedback to the investigator via the LCD monitor. Check your work regularly to ensure that your settings are appropriate for the lighting conditions. Use of the oncamera and off-camera flash when appropriate is imperative for correct illumination of the subject. Photographs should never be deleted, even when taken by mistake. Meta data embedded in the camera records each photograph and details about the settings, date and time. Deleted photographs could raise unwanted questions during deposition or trial and it is best to admit to an errant photograph than to explain why you deleted it. Module 2: Crime Scene Investigation Page 17 Bloodstain Interpretation Bloodstain Interpretation Blood evidence can provide information that can solve a case. Therefore correct documentation, collection, and preservation of this type of evidence is crucial. Improper handing of blood evidence can destroy its evidentiary value. Properly collected and preserved blood evidence can establish a link between an individual, a criminal act or a crime scene, and can be used to strengthen or contradict a witness or suspects statement or to eliminate a person as a potential suspect in a crime. Properly documented, collected, and stored blood evidence can be presented in a court of law several years from the time of a criminal act. Bloodstain Pattern Analysis The shape and distribution of blood drops and other patterns at a crime scene can be used to help reconstruct the mechanical causation of individual events and help narrow down how a crime occurred. The shape and appearance of bloodstains and smears can also provide useful information about a crime. In 1971, MacDonell outlined several general rules regarding blood spatter evidence and the general rules of blood spatter pattern recognition including spot shape, edge characteristics, spot diameter, angle of impact, degree of spatter, directionality, cast off droplets and various types of impact stain. For additional information on the historical aspects of the discipline of spatter pattern analysis see: https://science.howstuffworks.com/bloodstain-pattern-analysis4.htm (https://science.howstuffworks.com/bloodstain-pattern-analysis4.htm) The following topics are important: Basics of Bloodstain Pattern Analysis, including proper terminology Blood patterns on and around the body Blood patterns on walls, floors, furniture, ceiling, etc. Drip trails, pooling, void areas, projected blood patterns, transfers Back spatter and forward spatter created by gunshots Recommended current terminology can be found at https://hemospat.com/bloodstain-pattern-analysis-terminology/ (https://hemospat.com/bloodstain- pattern-analysis-terminology/) Collecting Blood Evidence Go to the following website on the Collection and Preservation of Blood Evidence from Crime Scenes at http://www.crime-scene-investigator.net/blood.html (http://www.crime-scene-investigator.net/blood.html). Read the sections entitled: Preliminary Considerations Collection and Preservation of Blood Evidence Dried Bloodstains Wet Bloodstains The section on luminol is important, as this is one of the most useful chemicals in detecting minute quantities of blood and can be used to locate blood in crevasses and in very minute traces where attempts have been made to clean up and conceal evidence. A newer reagent called Blue Star Forensic™ works similarly to luminol, but glows brighter and for longer periods of time allowing for easier documentation via photography. Luminol and Blue Star Forensic both cross-react with bleach, some plant peroxidases and some metals, so appropriate training and recognition of the differences between the types of reactions is necessary Module 2: Crime Scene Investigation Page 18 Motor Vehicle Investigation Motor Vehicle Investigation During a criminal investigation, a vehicle, which may or may not be the primary scene, may need to be processed. A vehicle may be part of the investigation because it was stolen, used as a getaway vehicle or used for some other crime, and processing requires the same caution and detailed examination as any other crime scene. An investigator must take care to document all steps of the investigation, make a detailed inventory of property in the vehicle and obtain all fragile evidence first (such as fingerprints). The types of evidence present will vary depending on the circumstances and nature of the crime. For detailed evidence searching the vehicle should be towed, if possible, to a police compound or well-covered area and a systematic search for evidence conducted. Burglary of the vehicle may yield fingerprint evidence, whereas a vehicle used for a murder to transport a victim may hold an array of physical evidence. Steps of Vehicle Processing 1. Initial examination 2. Written documentation of vehicle in original state 3. If towed to a secure facility, the vehicle must be sealed and photographed or escorted to the terminal location and a tow receipt signed 4. Systematic photographic and documentation, starting with the exterior, taken from each side, corners, front, rear, tag, including any decals, damage or custom accessories. The interior of the vehicle should be photographed from the front drivers area; from each side with the doors open, the ignition area, the dash, the glove box, the instrument panel, the rear seat area, and the trunk area 5. An organized section-by-section search should be conducted to find items of evidence not immediately obvious during the initial examination 6. Other items of evidence located during the search should be annotated with evidence markers and photographed to record location and relationship of any evidence found 7. Collection of evidence, beginning with the most fragile evidence (trace evidence), evidence easily lost, or susceptible to damage or loss through handling or weather conditions 8. Mechanical processing for any latent fingerprints. Common sense areas should be searched around the sides, hood, trunk, roof support post, and windows of the exterior of the vehicle. Inside, the door handles, rear view mirror, seat belt buckles, windows, should also be searched 9. Relevant control samples should be acquired, including glass samples, fiber samples for upholstery and carpet, chipped paint, and wiring for comparison with electronic components, like CD players and telephones that may have been stolen from the vehicle. For more detailed information on practical methods for processing a vehicle go to http://www.crime-scene-investigator.net/vehicleprocessing.html (http://www.crime-scene- investigator.net/vehicleprocessing.html). Abandoned Vehicles The process for evidence collection for abandoned vehicles is similar to that above, ensuring the location and detection of any physical evidence. A methodical search with detailed documentation should be conducted in a dry, protected, environment as weather can destroy vital evidence. The site where the vehicle is found should be photographed and sketches should include details of distance to the closest inhabited house or town. Other points to note are: Odometer readings Gas levels Appearance for reason for stopping there Damage Radiator temperature and ambient temperature to assist in determining the time of abandonment Homic

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