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2. FORENSIC SCIENCE • Is an applied science • Pure science seeks to understand the physical world for its own sake. • Applied science seeks to use physical principles to obtain a desired goal.

3. * Remember * Science is Dynamic • At any point in time, science gives our best estimate of how the universe works.

4. New discoveries may refine or refute what was considered to be “true”. • Understanding changes with new information. Examples –

5. Landmarks of Forensic Science • 1149 – Position of Coroner started by King Richard of England. • 1590 – Microscope developed by Zacharias Janssen of Holland.

6. 1670 – First powerful microscope created by Anton Van Leeuwenhoek. • 1732 Luigi Galvani discovered human nervous system transmits information electronically (lie detector)

7. 1807 – Forensic Science Institute opened at the University of Edinburg, Scotland. • 1823 – Whorls, ellipses, and triangles identified by Jan Evangelista Purkinjie.

8. 1836 – Method for detection of arsenic poison developed by Marsh of England. • 1850 – First private detective agency set up by Allen Pinkerton. • 1859 – Spectroscopy was developed by Kirchoff and Bunson.

9. 1880 – Sherlock Holmes detective stories published by Sir Arthur Conan Doyle. • 1888 – Hand held camera invented by George Eastman. • 1889 – Bullets are matched to the gun they were fired from.

10. 1892 – Scientific classification of fingerprints developed by Galton. • 1895 – X-rays discovered. • 1896 – System of matching fingerprints to identify people developed by Ed Henry.

11. 1901 – Human blood groups identified. • 1903 – NYC police begin fingerprint files of arrested persons. • 1909 – Chromosomes discovered to carry hereditary information.

12. 1910 – First forensic laboratory opened in France by Edmond Locard. • 1930 – National fingerprint file set up by FBI. • 1932 – FBI forensic laboratory established.

13. 1980 – Method for detecting DNA differences developed. • 1987 – First time DNA evidence is used to convict a person in U.S.

15. BASIC SERVICES PROVIDED BY A CRIME LABORATORY • Physical Science Unit – Applies principles and techniques of chemistry, physics, and geology to the identification and comparison of crime scene evidence.

16. Biology Unit – staffed with biologist and biochemist who apply their knowledge to the identification and DNA profiling of dried blood and other body fluids, and the comparison of hairs and fibers.

17. They also compare and identify botanical materials such as wood and plants.

18. Firearms Unit – conducts the examination of firearms, discharged bullets, cartridge cases, shotgun shells, and ammunition of all types. Clothing and other objects are also examined for residue and to approximate the distance from the fired weapon.

19. Document Examination Unit – Study handwriting and typewriting to determine authenticity and/or source. Analysis of inks, paper, erasures, and burned or charred documents.

20. Photography Unit – Uses digital imaging, infrared, ultraviolet and X-ray photography to make invisible evidence visible. Also help prepare photographs for courtroom presentations.

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22. Voice Analysis Unit –Analyzes tapes and recordings, voiceprints. Evidence Collection Unit – Dispatches specially trained personnel to the crime scene to collect and preserve evidence.

23. The Functions of the Forensic Scientist • Analysis of Physical Evidence. The procedures and techniques used in the lab must have a firm scientific foundation.

24. They must also be acceptable to the court. In the case Frye v. United States the courts said for a procedure, principle, or technique to be admissible it must be generally accepted by the scientific community.

25. In the 1993 case Daubert v. Merrell Dow Pharmaceutical, Inc. Supreme Court ruled that judges where to be “gatekeepers” in deciding the admissibility of scientific evidence and testimony.

26. The guidelines judges use to determine admissibility are • A. Has the technique or theory been tested? • B. Has the technique or theory been subject to peer review and publication?

27. C. What is the potential rate of error? • D. Have standards been applied to the technique? • E. Has the theory or method been widely accepted by the scientific community?

28. 2. Provide Expert Testimony Because their work may ultimately be used to determine a persons guilt or innocence, a forensic scientist may be required to testify in court about their methods and conclusions.

29. The courts take several things into consideration when deciding if a person is an expert. These may include questions, presentation of degrees or certificates, years of experience, or publication.

30. Both sides should agree to call a person an expert witness but the judge has final determination.

31. 3 Furnish training in the proper recognition, collection, and preservation of physical evidence.

32. Some other fields in forensic science include: • Forensic Pathology • Forensic Anthropology • Forensic Entomology • Forensic Psychiatry • Forensic Odontology • Forensic Engineering

33. FORENSIC PATHOLOGY • 1. Involves the investigation of sudden, unnatural, unexplained, or violent deaths. • 2. The major question to be answered is What caused the death?

34. 3. Sometimes the cause of death may be apparent, sometimes an autopsy may be required. An autopsy is the medical dissection and examination of a body in order to determine the cause of death.

35. http://www.nlm.nih.gov/visibleproofs/galleries/media/index.htmlhttp://www.nlm.nih.gov/visibleproofs/galleries/media/index.html

36. There are five categories that a death may fall into • Natural • Homicide • Suicide • Accident • Undetermined

37. 5. Decomposition process and time of death. • A. Immediately following death the muscles relax and then become rigid. This is called rigor mortis. It usually begins within 24 hours and disappears in about 36 hours.

38. B. Livor mortis is another useful tool in determining time of death. When the heart stops pumping blood it begins to settle in the areas closest to the ground due to gravity.

39. The skin in this area will become darker. This begins immediately after death and continues for up to twelve hours after death. Livor mortis is useful in determining if a body has been moved or changed position after death.

40. C. Other chemical and physical changes that occur after death may be useful in determining time of death. Algor mortis is the process in which the body loses heat after death until it reaches the same temperature as its surroundings.

41. The rate at which a body loses heat is determined by many factors such as the amount and type of clothing, weather conditions, and the size of the body. A body placed in water loses heat much faster than one on or above the ground.

42. As a general rule, beginning an hour after death the body loses heat at a rate of approximately 1 to 1½ degrees per hour until the environmental temperature is reached.

43. D. Another way to estimate the time of death is by determining the potassium levels in the fluid of the eye (vitreous humor).

44. FORENSIC ANTHROPOLOGY • Concerned primarily with the identification and examination of human skeletal remains. Because bones are so durable they can be used for a long time after death.

45. From the study of skeletal remains we can determine characteristics such as age, height, sex, race, physical condition and appearance.

46. Some specialize in facial reconstruction to aid in identification. Forensic anthropologist also identify victims of mass disasters by using bones collected from the scene.

47. Forensic Psychiatry • A specialized area in which the relationship between human behavior and legal proceedings is evaluated.

48. In criminal cases forensic psychiatrist evaluate behavioral disorders and help the courts determine if a person is competent enough to stand trial. They also examine behavioral patterns of criminals in order to develop a behavioral pattern.

49. Forensic odontology • They provide information about the identification of bodies in unrecognizable states. Teeth are made of enamel which is the hardest substance found in the body.

50. They usually survive. Dental remains can be identified by using dental records such as x-rays, dental castings, or photographs. Another important job of forensic odontology is in bite mark analysis.