Digging Deeper: Crime Scene Investigation PDF

DIGGING DEEPER Crime Scene Investigation The word “forensics” means to do with the law. CHECK YOUR UNDERSTANDING Therefore, forensic science means using scientific What does the term knowledge and techniques...

DIGGING DEEPER Crime Scene Investigation The word “forensics” means to do with the law. CHECK YOUR UNDERSTANDING Therefore, forensic science means using scientific What does the term knowledge and techniques to help with a criminal forensic science investigation, especially in a trial. Every day, mean? forensic scientists are hard at work in dedicated crime labs. They use tests to analyze evidence from crime scenes. If the tests they use reveal What is the role of a anything useful about a criminal case, the same forensic scientist? scientists are often also called upon to be expert witnesses in a trial. They will explain what the test results mean. This can make all the difference in proving whether a person is guilty What “evidence” is on or innocent. the floor around you? Take a break from reading for a minute. Look down at the floor. Do you see anything? If you Why is Dr. Edmond were able to look really closely, you would find Locard important to miniscule pieces of evidence that you have left the history of forensics? behind. It’s likely that your fingerprints, DNA, clothing fibers, and other pieces of evidence are around you. We leave a unique trace wherever What implications does Locard’s principle have we go. Dr. Edmond Locard, the founder of the on the field of first forensics laboratory, was the first person to forensics? state this fact. His principle, Locard’s Exchange Principle, states that every contact leaves a trace. This idea is helpful to forensic investigators who look for these traces to solve crimes. Forensic Fact #1 Forensic Fact #2 Forensic Fact #3 Crime scene investigators do not Forensic science wasn’t What piece of crime scene data is responsible for identifying over 93% clean up crime scenes when they invented by scientists. Police of remains? Dental records. Because are finished processing the officers were the first to bones are among the sturdiest parts scene. This job falls on the begin using science to solve of the body, they are often the best- owner of the property. crimes. preserved area in remains. © The Trendy Science Teacher 2018 DIGGING DEEPER Crime Scene Investigation When an investigator searches a crime scene, they CHECK YOUR UNDERSTANDING are looking for something specific - EVIDENCE. This How is evidence evidence comes in many forms. All evidence can be classified? classified as either direct evidence or circumstantial evidence. Direct evidence directly proves a fact or is a firsthand observation. Surveillance footage, What is the difference between direct and confessions, and eyewitness accounts can all be circumstantial presented in court as direct evidence. Circumstantial evidence? evidence is the most common evidence found at a crime scene and only implies a fact. Further investigative work is needed to determine the origin/source of this type of evidence. For example, fingerprints are considered to be circumstantial evidence because the print must be lifted and What is the most analyzed by a fingerprint examiner to determine the common type of source of the print. Other types of circumstantial evidence found at a evidence include DNA, casings, bite marks, tire crime scene? prints, hair, and unsigned ransom notes. Another way that we can classify evidence is by How does individual matching it to a donor. Sometimes, evidence can be evidence compare to class evidence? narrowed down to an individual person. We call this type of evidence individual evidence. Fingerprints and DNA are considered individual evidence because both fingerprints and DNA can be matched to a single person. Class evidence on the other hand, cannot narrow down the evidence to an individual, but can be linked to a group of people/objects. For What are some examples of class instance, if blood is found at a crime scene and the evidence? blood type is B+, then this blood type can be used to narrow down a suspect to a group of individuals with B+ blood. Other types of class evidence are footprints, tread patterns on tires, and hair without the root. All of these can narrow the suspect field but cannot directly link to an individual. © The Trendy Science Teacher 2018 Answer Key DIGGING DEEPER Crime Scene Investigation Answer Key The word “forensics” means to do with the law. CHECK YOUR UNDERSTANDING Therefore, forensic science means using scientific What does the term knowledge and techniques to help with a criminal forensic science investigation, especially in a trial. Every day, mean? Using scientific forensic scientists are hard at work in dedicated knowledge and crime labs. They use tests to analyze evidence techniques to help with from crime scenes. If the tests they use reveal a criminal investigation anything useful about a criminal case, the same What is the role of a scientists are often also called upon to be expert forensic scientist? witnesses in a trial. They will explain what the Use tests to link evidence to suspect, test results mean. This can make all the can be called into difference in proving whether a person is guilty court as an expert witness or innocent. What “evidence” is on the floor around you? Take a break from reading for a minute. Look Hair, fibers, Cheetos down at the floor. Do you see anything? If you crumbs (answers will were able to look really closely, you would find vary) miniscule pieces of evidence that you have left Why is Dr. Edmond behind. It’s likely that your fingerprints, DNA, Locard important to the history of forensics? clothing fibers, and other pieces of evidence are He established the first around you. We leave a unique trace wherever forensics lab. we go. Dr. Edmond Locard, the founder of the What implications does first forensics laboratory, was the first person to Locard’s principle have state this fact. His principle, Locard’s Exchange on the field of forensics? It is the Principle, states that every contact leaves a trace. reason that we search This idea is helpful to forensic investigators who for evidence and seek look for these traces to solve crimes. to link it to a suspect. Forensic Fact #1 Forensic Fact #2 Forensic Fact #3 Crime scene investigators do not What piece of crime scene data is Forensic science wasn’t invented responsible for identifying over clean up crime scenes when they by scientists. Police officers were 93% of remains? Dental records. are finished processing the the first to begin using science to Because bones are among the scene. This job falls on the solve crimes. sturdiest parts of the body, they owner of the property. are often the best-preserved area in remains. © The Trendy Science Teacher 2018 DIGGING DEEPER Crime Scene Investigation When an investigator searches a crime scene, they CHECK YOUR UNDERSTANDING are looking for something specific - EVIDENCE. This How is evidence evidence comes in many forms. All evidence can be classified? All evidence classified as either direct evidence or circumstantial is classified as direct or evidence. Direct evidence directly proves a fact or is circumstantial a firsthand observation. Surveillance footage, evidence. confessions, and eyewitness accounts can all be What is the difference presented in court as direct evidence. Circumstantial between direct and circumstantial evidence is the most common evidence found at a evidence? crime scene and only implies a fact. Further Direct evidence investigative work is needed to determine the directly proves a fact origin/source of this type of evidence. For example, and is considered a firsthand observation. fingerprints are considered to be circumstantial Circumstantial evidence because the print must be lifted and evidence only implies a analyzed by a fingerprint examiner to determine the fact. source of the print. Other types of circumstantial What is the most evidence include DNA, casings, bite marks, tire common type of prints, hair, and unsigned ransom notes. evidence found at a crime scene? Circumstantial Another way that we can classify evidence is by evidence matching it to a donor. Sometimes, evidence can be narrowed down to an individual person. We call this How does individual evidence compare to type of evidence individual evidence. Fingerprints class evidence? and DNA are considered individual evidence because Individual evidence both fingerprints and DNA can be matched to a can link directly to one individual while class single person. Class evidence on the other hand, evidence only narrows cannot narrow down the evidence to an individual, down the suspect field but can be linked to a group of people/objects. For to a group of instance, if blood is found at a crime scene and the individuals. blood type is B+, then this blood type can be used to What are some narrow down a suspect to a group of individuals with examples of class B+ blood. Other types of class evidence are evidence? footprints, tread patterns on tires, and hair without Blood type, tread patterns, hair without the root. All of these can narrow the suspect field the root but cannot directly link to an individual. © The Trendy Science Teacher 2018