Crime Scene Specialties 1

Crime Lab — Basic Services  Physical Science Unit  Chemistry  Physics  Geology  Biology Unit  Firearms Unit  Document Examination Unit  Photography Unit 2 Most crime labs are backlogged and there has been a “triage” system developed to help analyze the sample from the most “serious” cases, murder & sexual assault

Physical Science Unit Crime Lab —Basic Services 3 Applies principles of chemistry, physics and geology to identify and compare physical evidence such as: Drugs Glass Paint Explosives Soil

Biology Unit Crime Lab—Basic Services 4 Applies knowledge of biological sciences to investigate samples such as: Blood Body fluids (DNA) Hair Fibers Botanical samples (ex. wood, plants)

Firearms Unit Crime Lab—Basic Services 5 Examines: Firearms Discharged bullets Cartridge cases Shotgun shells Ammunition of all types Garments and other objects for firearms discharge residues Approximate distance from target to weapon

Document Examination Unit Crime Lab—Basic Services Studies handwriting and typewriting on questioned documents to determine authenticity and/or source Analyze paper and ink Examine indented writings, obliterations, erasures and burned or charred documents 6

Photography Unit Crime Lab—Basic Services 7 Use of highly specialized photographic techniques to make invisible information visible to the naked eye, such as: Infrared Ultraviolet X-ray photography Photographs crime scenes and physical evidence Prepares photographic exhibits for court

Photography Unit 8

Optional Services Provided by Full- Service Crime Lab Fingerprint Unit & Latent Fingerprint processes and examines evidence for latent fingerprints. Polygraph Unit conducts polygraph or lie detector tests. Voiceprint Analysis Unit attempts to tie a recorded voice to a particular suspect. Evidence-Collection Unit dispatches specially trained personnel to the crime scene to collect and preserve physical evidence. 9

10 An envelope containing anthrax spores along with an anonymous letter was sent to the office of Senator Tom Daschle shortly after the terrorist attacks of September 11, A variety of forensic skills were used to examine the envelope and letter. Also, bar codes placed on the front and back of the envelope by mail- sorting machines contain address information and information about where the envelope was first processed. Courtesy Getty Images, Inc.—Liaison Several Units coming together on 1 piece of evidence

Special Forensic Science Services  Forensic Pathology  Forensic Entomology  Forensic Odontology  Forensic Anthropology  Forensic Toxicology  Forensic Psychiatry  Forensic Engineering  Forensic Computer and Digital Analysis 11

Forensic Pathology Concerned with determining the cause of death Examines wounds and injuries 12 A forensic pathologist examines a kidney during an autopsy. “This is the place where the dead shall teach the living.”

Forensic Entomology Uses insects to help law enforcement determine the cause, location and time of death (TOD) of a human being Insect life cycles act as precise clocks which begin within minutes of death Used to determine the TOD when other methods are useless Insects can also show if a body has been moved after death 13

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Forensic Odontology Helps identifies victims based on dental evidence Bite mark analysis - compare marks left of a victim and the tooth structure of a suspect 15

Bite Marks 16 Pattern injury displaying ovoid pattern and central bruising Pattern injury displaying linear interrupted abrasions

Forensic Anthropology Assist in identification of deceased individuals whose remains are decomposed, burned, mutilated or otherwise unrecognizable 17 An anthropologist exhumes an unidentified set of remains from a Sarajevo cemetery. Forensic anthropology teams match these and thousands of other remains from conflicts around the world with DNA samples from family members of missing relatives. Photo by T.J. Grubisha 2002, U.S. State Department.

Forensic Toxicology The effects of poisons, toxins and drugs in the body. Blood & breath alcohol determination Urine & hair testing for a “drug-free workplace” “Date rape” drugs in a sexual assualt victim Not to be confused with “drug” analysis in the physical crime unit. Drug analysis is simply identifying the substance For example: is this white powder in fact cocaine 18

Forensic Psychiatry Examines relationship between human behavior and legal proceedings is examined Determine if person is competent to stand trial Examines behavior patterns of criminals as an aid to developing a suspect’s behavioral profile 19

Forensic Engineering Concerned with failure analysis accident reconstruction causes and origins of fires or explosion 20

Forensic Computer Science + Digital Analysis Identifying, collecting, preserving, and examining information derived from computers and other digital devices, such as cell phones Recovering deleted or overwritten data from a computer’s hard drive Tracking hacking activities within a compromised system 21

Expert Witness Everyone of these specialists could be an expert witness called to testify in court about the work they or someone else conducted in the lab. They are individuals who by knowledge, training or experience are qualified to discuss their experiences in court 22

Dr. Henry Lee Dr. Lee was an expert witness for several high profile cases, he is also one of the authors of your textbook 23

Dr. Jan Garavaglia (Dr. G) Dr. G’s (expert medical examiner) testimony during the Casey Anthony Trial in the death of Caylee Anthony her two-year old daugher who was missing for 31 days prior to contacting the police. 24