Intro to Forensic Science Week 1 PDF

Intro to Forensic Science: Week 1 In its broadest definition, forensic science is the application of science to crimminal and civil laws The subject matter of this book emphasizes the application of science to those crimial and civil laws that are enforced by police agencies in a criminal justice sy...

Intro to Forensic Science: Week 1 In its broadest definition, forensic science is the application of science to crimminal and civil laws The subject matter of this book emphasizes the application of science to those crimial and civil laws that are enforced by police agencies in a criminal justice system CSI Definition Forensic science owes its origins ot individuals such as Orfila, Bertiiion, Galton, Lattes, Goddard, Osborn and Locard, who developedthe principles and techniques needed to identify or compare physical evidence History (ONE MIDTERM QUESTION) Mathieu Orfila -The father of forensic toxicology (poisons) Alphonse Bertillon -Devised the first scientific system of personal identification in 1879 Francis Galton -Conducted the first definitive study of fingerprints and their classification Leone Lattes -Developed a procedure to determine blood type from dried bloodstains Calvin Goddard -Refined the technique of determining if a particular gun fired a bullet by using the comparison mircoscope Albert Osborn -Developed the fundamental prininples of document examination Walter McCrone -Advanced the field of microscopy and its application to examinn evidence Hans Gross -Wrote the first treatise describing the applicsiton of scientific principles to the field of criminial investigation Edmond Locard -Incorportated Gross’ Principles within a workable crime laboratory Alec Jefferys Locards Exchange Principle -States that when a person comes in contact with an object or another person, a cross-transfer of materials occurs The Crime Lab The ever increasing number of crime laboratories is partly the result of the following -Supreme Court decisions in the 1960s responsible for police placing greater emphasis on securing scientifically evaluated evidence -Crime laboratories inundated with drug specimens due to acdcelerated drug abuse -The advent of DNA profilling At present, approximately 411 public crime laboratories operate at various levels of government-federal, state, county, and municipal Crime Laboratory Units The technical support provided by crime labortoes can be assigned to five basic services The physical science unit incorporates the principles of chemistry, physics and geology to identify and compare physical evidence This many include the anayis of drugs, glass, paint, ecplosives, and soil The biology unit applies the knowledge of biological sciences in order to investigate biological fluids or touch samples for DNA, as well as compare hair and fiber samples The firearms unit investigates discharged buklets, cartridge cases, shotgun shells, and ammunition. Tool mark comparisons many also be made in this unit Crime Laboratory Unts The document examination unit provides the skills needed for handwriting analysis and other questioned- document issues such as obliterations, erasures, and burnt documents The photography unit applies specialized phtogrpahic techniques for recording and examining physical evidence Optional Services by Full-Service Labs -The toxicology unit examines body fluids and organs for the presence of drugs and poisons -The latent fingerprint unit processes and examines evidence for latent fingerprints -The polygraph unit conduits polygraph tests The voiceprint analysis unit attempts to link a recorded voice to a partivvular suspect The crime-scene investigation unit dispatches specially trained personnel to the crime scene to collect and preserve physical evidence Funcions of a Forensic Scientist A forensic scientist must be skilled in applying the principles and techniques of the physical and natural sciences to analyze the many types of evidcne that many be recovered during a criminal investigation The analysis of physical evidence requires that the techniques used first be tested using the scientific method Analyzing Physical Evidence Requires Utilizing the Scientific Method Formualte a question worthy of investigation Formulate a reasonable hypthesis to answer the question Test the hypothesis through experimentation Upon validation of the hypothesis, it becomes suitable as scientific evidence Functions of a Forensic Scientist A forensic scientist may also provide expert court testimony An expert witness is an indivudual whom the court determines possesses knowledge relevant to the trail that is not expected of the average person The expert witness is called on to evaluate evidence based on specilaize training and experience that the court lacks the ecpertise to do The expert will then express an opinion as to the significance of the findings Evidence Admissiblity: The Frye Standard The Frye v. Unites States decision set guidance for determining the admissibility of scientific evidence into the courtroom To meet the Frye standard, the evidence in question must be “generally accepted” by the scientific community Frye Not Absolute However in the 1993 case of Daubert v.Merrell Dow Pharmaceutical, Inc, the U.S Supreme Court asserted that the Frye standard is not an absolute prerequisite to the admissibility of scientif evidence Trial judges were said to be ultiamelty responsible as “gatekeeprs’ for the admissiblity and validity of scientific evidence presented in their courts, as well as all expert testimony Evidence Admissiblity: The Daubert Criteria In Daubert, the Supreme Court offered some guidelines as to how a judge can gauge the reliability of scientific evidence -Whether the scientific technique or theory can be (and has been) tested -Whether the technique or theory has been subject to peer review and publication -The techniques potential rate of error Existence and maintenance of standards controlling the techniques operation Whether the scientific theory or method has atrraccted widespread acceptance within a relevant scientific community Other Landmark Cases Kumho Tire CO. LTD V Carmichael determined that the the judge acts as a “gatekeeper” not only for scientific testimony. But any expert testimony Melendez-Diaz v. Massachusetts determined that an expert witness must appear in person to provide testimony in court so that the defnse has an opporuntiy to cross-examine the witness Evidence Collection Training Many crime laboratires have “evidence technicians” trained by the crime lab staff, on 24-hour call for evidence collection at crime scenes Training ensures all pertinent evidence will be recongnized and collected properly Where no formal training exist, familiarity can be gained through lectures, tours of the lab and evidence collection manuals Special Forensic Science Services A number of special forensic science services are available to the law enforcement community to augment the service of the crime laboratory -Forensic psychiatry -Forensic odontology -Forensic engineering -Forensic computer and digital analysis Forensic psychiatry is an area in which the relationship between human behaviour and legal proceedings is examined Foresnsic odoentolgoy involves using teeth to procide information about the identification of victims when a body is left in an unrecognizable state: also investigates bite marks, though this has become a ccontroverseial method of analysis Forensic engineering is concerned with failure analysis, accident reconstrution, and causes and orgins of fires or explosions Forensic computer and digital analysis involves the identification, collection, preservation and examination of digital evidence Midterm Chapter: 1, 2, 3, 5, 12, 13