Chapter 1 Introduction
- Forensic science is the application of science to law:
- Forensic science owes its origins to pioneers who developed the principles/techniques to identify or compare physical evidence.
- Mathieu Orfila (1813)-forensic toxicology
- Alphonse Bertillion (1879) -scientific system of personal identification
- Francis Galton-fingerprints and their classification
- Leone Lattes-blood type from dried bloodstains
- Calvin Goddard-firearms examination using microscope
- Albert Osborn (1910)-questioned document examination
- Walter McCrone-microscopy to examine evidence
- Hans Gross (1893)-described application of scientific principles to the field of criminal investigation
- Locard’s Exchange Principle -no two people/objects can come into contact with each without making some small changes (cross-transference)
- Sir Alec Jeffreys (1984)-first DNA profiling test
The Crime Lab in the U.S.
- Rapid growth/lack of national and regional planning/ coordination
The Crime Lab
- -Supreme Court requiring greater scientifically evaluated evidence
Technical Support for Labs
- -Physical Science Unit: chemistry/physics/geology
- -Biology Unit: investigate blood/body fluids/hair/fiber samples
- -Firearms Unit: discharged bullets/cartridge cases/ shotgun shells/ammunition
- -Document Examination Unit: handwriting analysis/questioned-documents
- Photography Unit: photographic techniques for recording/examining evidence
- Optional Services by Full-Service Labs
- -Toxicology Unit: drugs and poison
- -Fingerprint Unit: processes evidence for latent fingerprints/makes identifications
- -Polygraph Unit: polygraph tests
- -Voiceprint Analysis Unit: recorded voice to a particular suspect.
- -Crime Scene Investigation Unit: personnel to the crime scene to collect/preserve physical evidence.
SPECIAL FORENSIC SCIENCE SERVICES
- Forensic Psychiatry: relationship between human behavior/legal proceedings
- Forensic Odontology: teeth for identification/bite marks
- Forensic Engineering: failure analysis/accident reconstruction
- Forensic Computer/Digital Analysis Unit: examines digital evidence.
The Scientific Method
- 1. Formulate a question worthy of investigation.
- 2. Formulate a reasonable hypothesis to answer the question.
- 3. Test the hypothesis through experimentation.
- 4. Upon validation of the hypothesis, it become suitable as scientific evidence.
Skills of a Forensic Scientist
- 1. Scientific analysis of many types of evidence
- 2. Provide expert court testimony
- -to possess specialized training/experience the court lacks
- -express an opinion as to the significance of the findings
- -testifies beyond average (lay) witness
Frye v. U.S. 293 F1013 (1923)
- Established guidelines for determining the admissibility of scientific evidence into the courtroom
- -Frye standard: evidence must be “generally accepted” by scientific community
Daubert v. Merrell Dow Pharmaceutical, Inc., 509 U.S. 579 (1993)
- Supreme Court determined “ Frye standard” was not absolute prerequisite:
- -Trial judges were made “gatekeepers”
- -Responsible for admissibility/validity of scientific evidence/expert testimony
- 1. Technique/theory can be tested
- 2. Subject to peer review and publication.
- 3. Potential rate of error
- 4. Existence/maintenance of standards
- 5. Widespread acceptance within a relevant scientific community