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Introduction and History of Forensic Science What is Forensic Science? ● ● Knowledge and application of technology and science to criminal justice and law Use of chemistry, biology, physics, and geology with respect to data collection Sir Arthur Conan Doyle ● Sir Arthur Conan Doyle ● ● ● Influenced popularity of forensic science Used principles of serology, fingerprinting, firearm identification Creator of Sherlock Holmes Mathieu Orfila ● 1787-1853 ● Forensic toxicology ● Studied various poisons and effects on animals Alphonse Bertillon ● ● 1853-1914 Developed anthropometry ● ● Body measurements Precursor to fingerprinting Francis Galton ● ● 1822-1911 Standardized fingerprinting used for identification Leone Lattes ● 1887-1954 ● Blood Typing ● A, B, AB, O Calvin Goddard ● ● ● 1891-1955 Developed comparison microscope Firearms and bullet analysis Albert S. Osborn ● ● 1858-1946 Document examination ● Handwriting comparison ● Forgery ● Erasure ● Alterations Walter C. McCrone ● ● 1916-2002 Forensic Microscopy, analysis on shroud of Turin Edmond Locard ● 1877-1966 ● Founder of Criminalistic Institution in Europe ● Locard's Exchange Principle ● Cross-transfer of evidence USA! USA! USA! ● ● ● ● ● 1932, FBI and J. Edgar Hoover form a national forensics laboratory Became the world's largest and most extensive forensics lab Dedicated to training forensic scientists 320 crime labs operating on various levels in the US Services provided at each lab can vary Physical Science Unit ● Collection of physical evidence ● Drug, plant, soil, mineral Biology Unit ● ● ● ● Focus on biology and biochemistry DNA profiling from blood/bodily fluids Comparison of hair and fibers Plant and wood identification Firearms Unit ● ● Examines: ● Firearms ● Discharged bullets ● Cartridge cases ● Ammunitions Other weapons used in crimes Document Examination Unit ● Handwriting ● Typewriting ● ● Document authenticity Erased, burned, charred document recovery Photography Unit ● Examine and record crime scenes ● Digital imaging ● UV photo ● X-ray photo Toxicology Unit ● Body fluids and organs examined for drugs/poisons ● Alcohol ● Marijuana ● Stimulants ● Psychoactive Fingerprint Unit ● Process and examine fingerprints at crime scene Polygraph Unit ● ● ● ● Lie detector Used more by criminal investigator than forensic scientist Used during interrogation of witnesses and suspects Credibility issues Voice Analysis Unit ● ● ● Deals with telephone and tape recordings Utilizes a sound spectrograph Criticisms of validity and precision exist Admissibility and Reliability of Evidence ● Through court cases of Frye and Daubert guidelines for gathering evidence the technique: ● Has been tested ● Has been subject to peer review ● Has a low rate of potential error ● Has a standardized operating procedure ● ● Has widespread acceptance within the scientific community The trial judge has the authority to deem techniques valid and admissible Expert Witnesses ● Forensic scientists may be called to trial ● ● ● ● Must have demonstration of expertise via education, training, or experience Proof of competency can be ambiguous and difficult to prove Should not advocate for a witness but only provide expert opinion Differs from eye witness ● Eye witnesses can only express facts not opinions about the situation Crime Scene Investigators ● Professionals that recognize, collect, and preserve crime scene evidence ● ● Evidence collection manuals are widely available ● ● More skilled than police officers or detectives Describes proper collection and transfer of physical evidence FBI standard evidence collection manual can be found in Appendix I Forensic Pathology Forensic Pathology ● Usually deals with sudden, unnatural, unexplained, violent deaths ● Generally medical examiners or coroners ● Primary role is to determine cause of death ● ● What injuries are present? ● When, why, and how are the injuries produced Autopsies are performed if simple observation does not provide enough evidence for cause of death Forensic Pathology ● ● Time of death determined by stages of decomposition Rigor mortis ● ● ● 24-36 hours Muscles relax then become rigid without shortening Livor mortis ● Immediately-12 hours ● Collection of blood settling in liver ● Blood collects in parts of the body closest to ground Forensic Pathology ● Algor mortis ● ● ● Gradual cooling of body temperature until equilibrium with ambient temperature ● Used in determining time of death ● Loss of 1-1.5 degrees F per hour Potassium released in vitreous humor Stomach contents determine when last meal was consumed Forensic Anthropology ● ● ● Examination of skeletal bones Durability of bones can take decades and centuries to decay Info on age, race, sex, facial reconstruction ● Pelvic area differences Forensic Entomology ● Insects and relation to crime ● Blow flies used to estimate time of death based on life cycle stages Forensic Psychiatry ● ● Relationship between human behavior and legal proceedings Evaluate mental capacity to stand trial in civil cases ● Evaluate behavioral disorders for criminal cases ● Develop behavioral patterns of criminals Forensic Odontology ● Evaluation of dental remnants ● ● Enamel in teeth is the last body part to decay because of its strength Used to compare bite marks of teeth structure Case Study