Transcript Slide 1
The Pendergast Enrichment Program Investigates Forensic Science http://www.cbs.com/primetime/csi/main.shtml Forensic Science Forensic Science is the scientific examination of evidence in a criminal investigation. Easily put, it is the study of objects that relate to a crime evidence. Forensic scientists study evidence so that it can be used in court. The term forensic means “suitable for a court of law.” Crime Scene Investigation involves the use of scientific methods, physical evidence, deductive reasoning, and their interrelationships to gain explicit knowledge of the series of events that surround the commission of a crime. Locard’s Principle • The principle developed by Edmond Locard in 1910 states that criminals always take a trace of something with them or leave a trace of something behind at the scene of the crime. • Every time an individual comes in contact with a place or another individual, something of that individual is left behind at the place, and something of that place is taken away with the individual. • If your Aunt Bertha gives you a big hug and walks away, fibers from her clothes will be on your clothes and fibers from your clothes will be on hers. Your hair is constantly falling out (circle of life, guys). You leave it all over the place. Just look around your house. You pick up carpet fibers on your shoes, dirt from the ground. Your skin flakes off. Look at the Wayne Williams case in Atlanta. He was convicted because fibers found on the body of one of his victims matched fibers from the carpet in his house. Might not sound like much, but it's GREAT physical evidence. EVIDENCE Direct Evidence – Something that proves the fact without a doubt. For example: eyewitness to the crime or a videotape of the crime being committed. Circumstantial Evidence – Provides supporting facts to establish the truth thorough indirect means. For example: if a suspect recently bought the same type of poison or owns the same type of weapon that is involved in a crime. At The Crime Scene 1. 2. 3. 4. 5. 6. Check the victim Secure the area Always take pictures. They are the best record available. They show the crime scene as it was found; where objects are in relation to other objects, victims, rooms, etc. Take notes. Describe the scene, its over all conditions. Describe rooms, lights, shades, locks, food; anything that can indicate a time frame, condition of scene or that might have even the slightest evidentiary significance. Check dates on mail and newspapers. Diagram the crime scene. Take measurements. Photos are good to show where an object is in relation to another object, but measurements tell exactly how far. Interview any witnesses Collecting Evidence When police acquire evidence at a crime scene they follow certain procedures to make sure the evidence is preserved and documented. They typically do the following things. Police must be able to prove that evidence was always in their possession. 1. Each possible piece of evidence collected is put in its own container. The container is labeled and sealed. 2. The label indicates where and when it was found and is initialed by the officer who found it. 3. The evidence is then sent to the crime lab. Chain of Custody Chain of Custody is of paramount importance to any investigation. It is the unbroken sequence of events that is caused by an item of evidence from the time it is found at the crime scene to the time it appears in court. Every link in this chain is documented, from discovery at the crime scene, through evidence gathering, storage, lab analysis, return to storage, transfer to court. Every link is documented by date, time, handling individual, what was done with the evidence by that individual. If chain of custody is broken, if the evidence cannot be accounted in one step of its journey from crime scene to court room, it is rendered inadmissible; useless to the case. At The Forensic Lab Once the evidence is received at the evidence lab the following procedures are taken. 1. Each object is listed in the evidence register. 2. Evidence is kept in a locker room. Only authorized people can examine it. 3. An exact record is kept of each person who has handled the evidence. 4. Evidence is examined by people who are specially trained to analyze and interpret it. 5. Forensic scientists at the crime lab use their skills in classification, comparison, observation, and reconstruction to examine the evidence. 6. Inferences based on the evidence are used in solving the crime. Frye Rule The Frye Rule states that in order for a new scientific technique to be used as evidence in court, it must be accepted by the scientific community as dependable and accurate. The name of the rule comes from the 1923 court case where the court rejected the scientific validity of the polygraph instrument. Scientific Method When detectives are trying to solve a crime, they use the scientific method. This method is commonly used by scientists to observe what is happening and then test various explanations. It consists of these five steps: 1. 2. 3. 4. 5. Gather as much evidence as possible Study all available evidence. Look for errors or inconsistencies. Form a hypothesis or explanation. Test the hypothesis in all possible ways. Forensic Science – An Adventure Forensic science is the use of science as it applies to the legal system and as science is used to solve crimes. Forensic Scientists use their knowledge of science to help determine the facts and the truth in both civil and criminal matters. Disciplines – There are a variety of careers involving different branches of science within the field of forensic science. There are careers to appeal to a wide variety of interests and abilities. A crime investigation could use any or all of the following specialists: Criminalist A criminalist examines and interprets physical evidence. Criminology – The scientific study and investigation of crime and criminals. Odontologist An odontologist is a dentist who applies the principles of dentistry to identify human remains and bite marks. Anthropologist An anthropologist is someone who is trained in social science. This person applies his or her knowledge of human development to identify skeletal remains and determine gender, age, race, or marks of trauma. The identification of skeletal, badly decomposed, or otherwise unidentified human remains is important for both legal and humanitarian reasons. Forensic anthropologists apply standard scientific techniques developed in physical anthropology to identify human remains, and to assist in the detection of crime. Forensic anthropologists frequently work in conjunction with forensic pathologists, odontologists, and homicide investigators to identify a decedent, the manner of death, and/or the postmortem interval. In addition to assisting in locating and recovering suspicious remains, forensic anthropologists work to suggest the age, sex, ancestry, stature, and unique features of a decedent from the skeleton. Pathologist A pathologist is a medical doctor who determines the cause of death by performing and autopsy. Forensic Engineer A forensic engineer is someone who has been trained as an engineer and who applies engineering concepts in legal situations (for instance, accident reconstruction or failure analysis). Deal with traffic accidents, fire investigations, and a variety of wrongful injury cases. The work is much like that of the crime scene examiner but with fewer bodies and better hours and generally much higher pay. Ballistic Analyst A ballistic analyst examines guns and ammunition and uses his or her expertise to interpret gunshot wounds. Also included in this broad subject area are explosives, imprint evidence and toolmark evidence. Serologist A serologist is a medical specialist who identifies and examines blood an other body fluids. Determination of the type and characteristics of blood, blood testing, bloodstain examination, and preparation of testimony or presentations at trial are the main job functions of a forensic serologist, who also analyzes saliva and other body fluids and may or may not be involved with DNA typing. It must be recognized, however, that in many crime labs, there may be no clear distinction between job title and job function. Psychiatrist A psychiatrist is a medical doctor with an advanced degree in psychiatry. He or she analyzes human behavior to determine what motivates a criminal, determines competence, and assesses the mental state of the accused. A forensic psychiatrist is a physician who integrates clinical experience, knowledge of medicine, mental health, and the neurosciences to form an independent, objective opinion. Document Examiner A document examiner is an expert in analyzing written evidence. This person studies handwriting, typewriting, photocopying and computer printers, forgery, paper and inks, writing instruments, computer disks, gambling machinery, stamps (as in the rubber pad kind) and the dating of documents. . Toxicologist A toxicologist is a scientist whose specialty is poisons. A toxicologist determines if drugs or other chemicals (poisons) contributed to the cause of death or were present in the crime. Becoming a Forensic Scientist Educational requirements will vary depending on specific careers, but some of the common requirements for most jobs in forensic science are: • A bachelor’s degree is a minimum requirement for most jobs. This degree could be in chemistry, biology, physics, police science or anthropology • A medical degree is necessary for some careers. In addition to formal training, other requirements might include: • Lot of science and math • Continuing education to keep current on new procedures • Board certification Special Skills Being a successful forensic scientist involves more than just getting a degree. Certain skills are a must: • • • • • • Good eyesight and keen observation skills Curiosity and imagination Ability to work with details Integrity Being objective and free from bias and prejudice Ability to keep accurate records A forensic scientist might also need to be skilled in public speaking, data management, and scientific writing The Work Place Forensic scientists may work in a variety of places and for different agencies. They can work in any of these capacities or workplaces: • For local, state or federal government • For a laboratory that analyzes different types of evidence • As an independent consultant • In a hospital, office, morgue or medical examiners office • At the crime scene or university Assignment #1 Have you ever wanted to be a mystery writer? Well, here is your chance…Use the information you learned about careers in forensic science to write your own crime story. Write about one crime that would involve the expertise of any three of these experts: Orthodontist, ballistics analyst, criminalist, anthropologist, pathologist, forensic engineer, serologist, toxicologist, document examiner, psychiatrist. Assignment #2 Choose any one career in forensics or crime investigation. Find out the job’s educational requirements, what exactly the person with this job does, what someone in this position might earn, and the benefits and drawbacks of the job. Either prepare a report that gives information about the job or create a help-wanted ad for the job. Explain why you would or would not want the job. These sites contributed a great deal to the info in this presentation: http://home.earthlink.net/~thekeither/Forensic/forsone.htm http://www.tncrimlaw.com/forensic A lot more can be found on the world wide web regarding forensic science and career possibilities. Hopefully you are inspired to learn more and enjoy the rest of this unit.