Introduction to Forensics September 7, 2005 Mr. Schildknecht SUPA Forensics The Science Behind Catching Criminals

Overview Definition of Forensic Science  Scope History and Development of Forensics Organization of a Crime Laboratory Functions of the Forensic Scientist  Analysis of Physical Evidence  Provision of Expert Testimony  Furnishing Training Scientific Admissibility

Definition and Scope of Forensic Science Forensic science is the application of science to those criminal and civil laws that are enforced by police agencies in a criminal justice system.

History Alphonse Bertillon ( )  First scientific system of personal identification  Developed the science of anthropometry, a systematic procedure of taking a series of body measurements as a means of distinguishing one individual from another

Bertillon Measurements

History, Con’t Edmond Locard ( )  Locard’s Exchange Principle –the exchange of materials between two objects that occurs whenever two objects come in contact with one another. A cross-transfer of evidence occurs.

Organization of Crime Labs General Organization  No nationally organized system— crime labs mirror the fragmented law enforcement structure that that exists on national, state, and local levels National Level  four major federal crime labs, FBI, DEA, ATF, US Postal

Organization, Con’t FBI (Department of Justice)  Largest crime lab in the world  Broad investigative powers DEA (Drug Enforcement Agency)  Responsible for the analysis of drugs seized in violation of laws regulating the production, sale, and transportation of drugs

Organization, Con’t ATF (Bureau of Alcohol, Tobacco, Firearms, and Explosives)  Responsible for the analysis of alcoholic beverages, weapons, and explosives in conjunction with the Gun Control Act and Organized Crime Control

Organization, Con’t State Level  Most state governments maintain a lab to service state and local law enforcement  Some larger cities maintain their own crime lab, usually under the direction of local police dept.

Organization Con’t Local Level  Local labs provide services to county and municipal agencies.  Generally, they operate independently of state labs and are financed by local government.

Services of the Crime Lab

Functions of the Forensic Scientist Analysis of Physical Evidence  Applies the principles and techniques of the physical and natural sciences to the analysis of evidence  Must be aware of the demands and constraints of the judicial system  Scientific procedures and techniques must satisfy the criteria of admissibility established by the courts

Functions Con’t Provision of Expert Testimony  May be required to testify with respect to methods and conclusions at a trial or hearing. Furnish Training  Train law enforcement in the proper recognition, collection, and preservation of physical evidence

Scientific Admissibility Frye Standard  Court must decide if a questioned procedure, technique, or principles are “generally accepted” by a meaningful segment of the scientific community  In practice, this has meant providing experts to testify that the procedure is generally accepted  Courts have also taken note of books, papers, and past judicial decisions in this regard

Admissibility, Con’t Daubert Standard  Court decides on the admissibility of science in the courtroom  “General Acceptance” is not an absolute prerequisite for admissibility  To ascertain the veracity of scientific evidence presented the judge should use the following areas of inquiry

Daubert Criteria Technique or theory can be (and has been) tested Technique or theory has been subject to peer review and publication Technique’s potential rate of error Existence and maintenance of standards controlling the technique’s operation Method or theory has attracted widespread acceptance within a relevant scientific community