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Warm- Up: Find the 6 differences between the two pictures. Source:

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1 Warm- Up: Find the 6 differences between the two pictures. Source: http://www.slylockfox.com/arcade/6diff/index.html

2 The answers are … Source: http://www.slylockfox.com/arcade/6diff/index.html Answers: Apple, branch, tree root, beaver’s ear, wood chips, snake

3 Objective SWBAT describe proper techniques for packaging common types of physical evidence.

4 Agenda 1.Physical Evidence 2.The Murder Scene 3.JonBenet Ramsey Documentary 4.Exit Slip

5 SEARCH METHODS  Line or strip method—best in large, outdoor scenes  Grid method—basically a double-line search; effective, but time-consuming  Zone method—most effective in houses or buildings; teams are assigned small zones for searching  Spiral method—may move inward or outward; best used where there are no physical barriers

6 Types of Evidence Two general types:  Testimonial—a statement made under oath  Direct evidence or Prima Facie evidence  Physical—any object or material that is relevant in a crime  Indirect evidence  Examples: hair, fiber, fingerprints, documents, blood, soil, drugs, tool marks, impressions, glass.

7 Value of Physical Evidence  Generally more reliable than testimonial  Can prove that a crime has been committed  Can corroborate or refute testimony  Can link a suspect with a victim or with a crime scene  Can establish the identity of persons associated with a crime  Can allow reconstruction of events of a crime

8 Reconstruction Physical Evidence is used to answer questions about:  what took place  how the victim was killed  number of people involved  sequence of events A forensic scientist will compare the questioned or unknown sample with a sample of known origin.

9 Types of Physical Evidence  Transient Evidence—temporary; easily changed or lost; usually observed by the first officer at the scene  Pattern Evidence—produced by direct contact between a person and an object or between two objects  Conditional Evidence—produced by a specific event or action; important in crime scene reconstruction and in determining the set of circumstances or sequence within a particular event  Transfer Evidence—produced by contact between person(s) or object(s), or between person(s) and person(s)  Associative Evidence—items that may associate a victim or suspect with a scene or each other; ie, personal belongings —Lee and Labriola in Famous Cases, 2001

10 Examples of Transient Evidence  Odor—putrefaction, perfume, gasoline, urine, burning, explosives, cigarette or cigar smoke  Temperature—surroundings, car hood, coffee, water in a bathtub, cadaver  Imprints and indentations— footprints, teeth marks in perishable foods, tire marks on certain surfaces  Markings

11 Examples of Pattern Evidence Pattern Evidence—most are in the form of imprints, indentations, striations, markings, fractures or deposits.  Clothing or article distribution  Gun powder residue  Material damage  Body position  Tool marks  Modus operandi  Blood spatter  Glass fracture  Fire burn pattern  Furniture position  Projectile trajectory  Tire marks or skid marks

12 Examples of Conditional Evidence  Light—headlight, lighting conditions  Smoke—color, direction of travel, density, odor  Fire—color and direction of the flames, speed of spread, temperature and condition of fire  Location—of injuries or wounds, of bloodstains, of the victim’s vehicle, of weapons or cartridge cases, of broken glass  Vehicles—doors locked or unlocked, windows opened or closed, radio off or on (station), odometer mileage  Body—position, types of wounds; rigor, livor and algor mortis  Scene—condition of furniture, doors and windows, any disturbance or signs of a struggle

13 Classification of Evidence by Nature  Biological—blood, semen, saliva, sweat, tears, hair, bone, tissues, urine, feces, animal material, insects, bacterial, fungal, botanical  Chemical—fibers, glass, soil, gunpowder, metal, mineral, narcotics, drugs, paper, ink, cosmetics, paint, plastic, lubricants, fertilizer  Physical—fingerprints, footprints, shoe prints, handwriting, firearms, tire marks, tool marks, typewriting  Miscellaneous—laundry marks, voice analysis, polygraph, photography, stress evaluation, psycholinguistic analysis, vehicle identification

14 Evidence Characteristics  Class—common to a group of objects or persons  Individual—can be identified with a particular person or a single source Blood DNA TypingFingerprints

15 Class vs Individual Evidence Which examples do you think could be individual evidence?

16 COLLECTING AND PACKAGING EVIDENCE  One individual should be designated as the evidence collector to ensure that the evidence is collected, packaged, marked, sealed, and preserved in a consistent manner  Each item must be placed in a separate container, sealed, and labeled  Most fragile is collected and packaged first  Different types of evidence require specific or special collection and packaging techniques  The body is the property of the coroner or medical examiner. The collection of evidence on the body is done by that department

17 PACKAGING Most items should be packaged in a primary container and then placed inside a secondary one. These are then placed inside other containers such as paper bags, plastic bags, canisters, packets and envelopes depending on the type and size of the evidence.

18 CHAIN OF CUSTODY There must be a written record of all people who have had possession of an item of evidence.  The evidence container must be marked for identification  The collector’s initials should be placed on the seal  If evidence is turned over to another person, the transfer must be recorded.

19 THE MEDICAL EXAMINER AND THE CORONER  A medical examiner is a medical doctor, usually a pathologist and is appointed by the governing body of the area. There are 400 forensic pathologists throughout the U.S.  A coroner is an elected official who usually has no special medical training. In four states, the coroner is a medical doctor.

20 MEDICAL EXAMINER’S RESPONSIBILITIES  Identify the deceased  Establish the time and date of death  Determine a medical cause of death—the injury or disease that resulted in the person dying  Determine the mechanism of death—the physiological reason that the person died  Classify the manner of death  Natural  Accidental  Suicide  Homicide  Undetermined  Notify the next of kin

21 PEOPLE IN THE NEWS Dr. Michael M. Baden is a renowned pathologist and was the Chief Medical Examiner in NY City and for Suffolk County. Dr. Baden was on the panel that investigated the assassinations of president John F. Kennedy and Dr. Martin Luther King, Jr. He has been involved as an expert in forensic pathology in many cases of international interest including: The remains of Tsar Nicholas of Russia and his family The Claus Von Bulow murder trial Expert witness for the defense in the O.J. Simpson trial Re-autopsy of Medgar Evers, Civil Rights leader Re-examination of the Lindberg Kidnapping and murder Autopsies of the victims of TWA Flight 800 Dr. Baden is the host of HBO’s Autopsy series and is featured on many of the crime talk shows.HBO’s Autopsy

22 JonBenet Ramsey Documentary 8. What did the autopsy reveal? 9. What was the largest problem with the investigation? 10. What were some problems with the investigation in the spring of 1997? 11. What clue did DNA testing give investigators? 12. Who did the handwriting analyst think the ransom note was written by? 13. Why were the Ramsey’s never called to testify in front of the grand jury?

23 JonBenet Ramsey Documentary 14. What did the grand jury decide on October 1999? 15. What was DA Keenan’s theory that was released in 2003? 16. Why was Carr arrested and why was the case dropped? 17. In 2008 what did the DNA reveal?

24 Homework Chapter 1 Review Questions, #1 – 29 & Chapter 2 Review Questions, # 1 – 26 due Thursday Units 1 – 2 Exam on Thursday!

25 Exit Slip September 2, 2014 1. Get out a mobile device or use one of the computers and go to m.socrative.com. You can also use one of the iPads that has the Socrative app. 2. When prompted, enter 417101 for the room number. QUESTION: Why should all items of evidence be placed in different containers?


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