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1 Introduction to Forensics Come in and get your notebooks out. We have notes today!

2 Forensics. What is FORENSIC SCIENCE? Forensics includes the application of a broad range of science to answer questions in the legal system. * Forensics is the application of science to criminal and civil law enforced by police in a criminal justice system. * Incorporates techniques of Chemistry, Biology, Physics, Geology, Computer Tech to determine value (significance) of crime scenes or evidence. * Forensics has extended to areas of pathology, psychology, anthropology, odontology that are used in the capacity of law enforcement.

3 Criminalistics vs Forensics You may hear the term criminalistics and forensics used in this class. Although there is overlap, the two terms are in fact different. Criminalistics focuses only on the scientific approach to examine crime scenes and evidence (Bio, Chem, Phys, Geol, etc). Forensics uses a variety of techniques and principles to study evidence. Forensics also incorporates psychology, accounting, computer science, etc. Criminalistics is only a branch of Forensic Science. FORENSICS Criminalistics

4 Common Branches of Forensic Science Pathology Odontology Psychiatric Crime Scene Studies injury patterns and determines cause of death Uses Dental information to identify bodies Studies human behavior Examines and collects evidence in a crime scene. Digital Media Photographs physical evidence and examines computer records Ballistics Examines fired guns and ammunition Toxicology Looks into detection of poisons Questioned Documents Analyzes ink, paper, toner and handwriting

5 History of Forensics First Use of Forensics Yi Yu Ji - Coroner Solved a Case using Pigs 700 Chinese begin use of Fingerprints for Identification 1775 Carl Wilhem Steel First test that detects arsenic in corpses Mathieu Orfila Father of toxicology. Published a book on the effects of poisons on animals. Toxicology evidence first used in 1839 Forensic Photography Introduced- Recorded inmate pictures and crime scene photos. Alphonse Bertillon Father of Anthropometry Used body measurements for identification. This was replaced by fingerprints.

6 History of Forensics Hans Gross wrote a book about how science can help with criminal investigations Sir Arthur Conan Doyle- made foresnics popular with Sherlock Holmes Books. First to apply Serology (Study of bodily fluid) 1901 Dr. Karl Landsteiner First to discover that blood can be seperated into 4 types A, B, O, and AB Albert Osborn Document Examination Edmond Locard Started first crime lab in an attic. Locard Exchange Principle states when two objects interact, they is an exchange of particles. So, all criminals pick up trace particles of the surrounding areas.

7 Locard s Exchange Principle "Wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as a silent witness against him. Not only his fingerprints or his footprints, but his hair, the fibers from his clothes, the glass he breaks, the tool mark he leaves, the paint he scratches, the blood or semen he deposits or collects. All of these and more, bear mute witness against him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It is factual evidence. Physical evidence cannot be wrong, it cannot perjure itself, it cannot be wholly absent. Only human failure to find it, study and understand it, can diminish its value." Beginning of Trace Evidence

8 History of Forensics Dr. Walter C. McCrone Pushed for microscopy in Forensics. Using microscopes to examine trace evidence. Calvin Goddard Ballistics looking at marking made by guns on bullets and bullet casings 1984 Sir Alec Jefferies Invented DNA profiling. Revolutionized Forensic Science. In 1986, DNA was used in court for the first time.

9 Introduction to Forensics

10 The Crime Lab Crime Labs are centers for both forensic investigation of ongoing criminal cases and research for new techniques for the future 4 Major Crime Labs FBI DEA AFT USPIS

11 FBI DEA AFT USPIS Federal Bureau of Investigations Drug Enforcement Administration Bureau of Alcohol, Firearms, Tobacco, and Explosives United States Postal Inspection Service Largest Crime lab in the World Used to Train personnel Analyzes drugs that are taken in violation of Federal laws Examines weapons and explosives Analyzes Alcohol and Tobacco Investigates any crime involving the post office Develops newest methods of testing Although these labs exist, many local law enforcement jurisdictions (city, county, state) run their own independent crime labs

12 Services of The Crime Lab Physical Evidence Analysis Evidence Collection Unit Biology / Pathology Unit Ballistics Unit Document Examination Unit Photography Unit Toxicology Unit Latent Fingerprinting Polygraph Voiceprint Analysis

13 Basics of Forensic Law

14 Methods of Crime Solving 3 main methods to solve crimes Confessions Trained law enforcement uses proper interrogation techniques. Ensures that confessions are free from coercion. Eye Witness Accounts Trained law enforcement to properly questions eye witnesses without leading them into giving information. Physical Evidence Trained law enforcement collects evidence and ensures it follows the proper chain of custody. Forensic Scientists focus on Analyzing Physical Evidence. They may be required to testify at a trail or hearing. They may train law enforcement in the collection and preservation of physical evidence.

15 Confession Suspects may confess on their own or after being interrogated. Confessions can be tricky and still need to investigated. It is important that the suspect is reliable, mentally stable, and in no way coerced or feeling threatened to make a confession.

16 Types of Witnesses Expert Witness Lay Witness will need to be educated, have experience, and training relevant to the trial. This person may express personal opinions to significance of special findings must testify on events or observations that come from personal knowledge (must be factual, no personal opinion of witness)

17 Collection of Physical Evidence Whenever evidence needs to be collected, trained personnel must be called to the scene. Crime Scene Units are trained to recognize and gather evidence. If CSU s are not available, officers or detectives collect evidence. Some police forces do not use crime scene units this can lead to problems later if proper collection techniques are not followed or there is an inconsistences in evidence chain of custody.