Chapter 1 Introduction to Forensic Science

Forensic Science Application of science to law Begins at crime scene Also known as Criminalistics

History of Forensics

Alphonse Bertillon Father of Criminal Identification Developed ANTHROPOMETRY

Anthropometry Series of body measurements to distinguish between individuals

Francis Galton Studied fingerprints & how to classify them

Calvin Goddard Firearms examiner Studied bullet comparison (Done today with a comparison microscope)

Edmond Locard Started the 1 st crime lab (France) Developed the Exchange Principle

Locard’s Exchange Principle When 2 objects come into contact, there is an exchange of materials between them (Cross-transfer of evidence) Criminals can be connected to a crime by particles carried from the crime scene

Crime Laboratories A. National B. State C. Local

National Labs (4) 1. Federal Bureau of Investigation (FBI  largest lab in the world) 2. Drug Enforcement Administration (DEA) 3. Bureau of Alcohol, Tobacco, Firearms, & Explosives (ATF) 4. U.S. Postal Inspection Service

State Labs Service the state as well as local communities that cannot afford their own crime lab

Local Labs Service counties & municipal (cities) agencies Financed by local government Nassau & Suffolk County Crime Labs

Basic Crime Lab Services 1. Physical Science Unit 2. Biology Unit 3. Firearms Unit 4. Document Examination Unit 5. Photography Unit

Physical Science Unit Uses chemistry, physics, and geology to identify & compare evidence

Biology Unit Examines blood & other body fluids DNA profiles Compares hair & fibers Examines botanical materials (plants/wood)

Firearms Unit (Ballistics) Examines firearms, discharged bullets, cartridge cases, & shotgun shells Searches clothing for gunpowder residue Determines distance a weapon was fired from

Document Examination Unit Studies handwriting or typewriting Analyzes paper & ink Examines indented writings & burned documents

Photography Unit Examines & records physical evidence Only black & white photos are shown to jurors

Optional Services 1. Toxicology Unit  poisons/drugs 2. Latent Fingerprint Unit 3. Polygraph Unit  lie detector 4. Voiceprint Analysis Unit 5. Evidence Collection Unit  CSI

Evidence & the Courts

Frye vs. United States (1923) Rejected lie detector evidence Scientific techniques, procedures, & principles must be “GENERALLY ACCEPTED” by majority of scientific community

Daubert vs. Merrell Dow Pharmaceuticals (1993) “GENERAL ACCEPTANCE” is no longer absolute Trial judge will act as GATEKEEPER  deciding whether evidence is admissible or not

The Expert Witness A person with knowledge that is not expected from the average individual This is acquired through experience, training, education, or a combination of all 3

Testimony Ordinary witnesses cannot & must not give their opinions  just FACTS Expert witnesses can give their opinions based on scientific facts (but can’t be biased to either side)

Other Areas of Forensic Science

Forensic Pathology Investigates sudden, unnatural, unexplained, or violent deaths Tries to answers Who? What? When? Why? How? Via Autopsy

Types of Death Natural Accidental Homicide Suicide Undetermined????

Estimating Time of Death

Rigor Mortis Muscles shorten & body stiffens Appears within 24 hours Disappears within 36 hours

Livor Mortis Blood settles to areas closest to ground Skin turns a blue/purple color

Algor Mortis Body starts to lose heat 1-1.5°F per hour until room or outside temperature is reached

Potassium Levels Rise in ocular (eye) fluid after death Time of death estimated by amount of potassium present

Forensic Anthropology Identifies & examines human skeletal remains Determines race, sex, age, & injuries Creates facial reconstructions

Forensic Entomology Studies insects & their relation to death Blow flies lay eggs  maggots

Forensic Psychiatry Determines if people are competent enough to make decisions or stand trial Develop behavioral profiles

Forensic Odontology Studies teeth & bite marks Useful when a body is unrecognizable

Forensic Engineering Determines how a crime happened & who is responsible Accident reconstruction