Presentation is loading. Please wait.

Presentation is loading. Please wait.

Chapter 3: THE CRIME SCENE “ Oh, how simple it would all have been had I been here before they came like a herd of buffalo and wallowed all over it.” —A.

Similar presentations


Presentation on theme: "Chapter 3: THE CRIME SCENE “ Oh, how simple it would all have been had I been here before they came like a herd of buffalo and wallowed all over it.” —A."— Presentation transcript:

1 Chapter 3: THE CRIME SCENE “ Oh, how simple it would all have been had I been here before they came like a herd of buffalo and wallowed all over it.” —A. Conan Doyle, in The Boscombe Valley Mystery, 1892

2 1. Secure and isolate the crime scene

3 FIRST OFFICER ON THE SCENE A Assess the crime scene and assist those hurt D Detain the witness A Arrest the perpetrator P Protect the crime scene T Take notes

4 2. Record the scene Photography  Digital camera should have 4 or more megapixels, close-up capabilities, and flash attachment (The more pixels, the more detail captured)  Differences in pixels are important in court because the greater the pixel the larger the print can be.

5 Photography Two photos should be taken of each shot in case one is blurred. There are three 3 general categories of photographs: 1. Overview (gives general locale and approach route) 2. Mid-range (mid-range (10-20 feet) tell a story that helps establish the modus operandi of the offender.) 3. Close-up (essential for establishing the corpus delicti of a criminal act.) *corpus delicti – the body of facts that show a crime was committed, includes the physical evidence and/or the body

6 There are two 2 general methods of photography: (1) overlapping, which is a series of photos taken in a circular or clockwise direction, overlapping each slightly to show the overall scene (2) progressive, which starts from a fixed point, photographs each piece of evidence as the photographer moves toward it, and progressively gets closer in the pictures.

7 Photography Bodies are photographed from five angles: (1) head to feet (2) right side (3) feet to head (4) left side (5) straight down from above

8 Notes (written observations) Constant Detailed Location Time How and by whom item was packaged Disposition of the item Tape-recorded Videotape

9

10 Sketches (drawn observations) Begin with rough sketch Accurate dimensions Location of all objects having a bearing on the case Letters/numbers assigned to items and include legend Compass heading north Finished sketch Drawn carefully Drawn to scale Computer aided drafting

11

12 Practical measuring techniques 1.Rectangular coordinates: This is the easiest and most used method for most crime scene specialist. Measurements are taken from 2 fixed areas at right angles of each other. 2. Triangulation coordinates: This method is designed to measure to an item from 2 fixed points by forming a triangle. Smeasurement.html

13 3. Conduct a systematic search for evidence Line method – used for outdoor scenes and involves lanes or strips to be searched by one searcher

14 Grid method – used for outdoor scenes and combines a strip search w/an additional strip search conducted at right angles to the 1 st

15 Zone method – used for outdoor or indoor and involves dividing scene into sectors which can be searched by a variety of investigators

16 Spiral method – used for large outdoor scenes and consists of starting at the center and following a spiral path out to the perimeter of scene

17 To be collected Victim’s clothing Fingernail scrapings Head and pubic hairs Blood Vaginal, anal, and oral swabs Recovered bullets from the body Hand swabs from shooting victims

18 4. Obtain Standard/Reference Samples Physical evidence whose origin is known, such as blood or hair from a suspect, that can be compared to crime- scene evidence Substrate controls – uncontaminated surface material close to an area where physical evidence has been deposited

19 5. Collect and Package Physical Evidence Must prevent contamination, breakage, evaporation, accidental scratching or bending, or loss through improper or careless packaging Entire object should be sent Package evidence separately Secure container

20 Special Considerations for Packaging Wet items must be dried before packaging to prevent mold and mildew Containers should be tightly sealed to prevent leaks Clothing with trace evidence should be packaged carefully Arson evidence should be kept in an airtight glass container to prevent fumes from evaporating

21 6. Maintain 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.

22 7. Submit Evidence to the Laboratory Personal delivery or by mail Must adhere to postal regulations Care taken in packaging

23 8. Crime Scene Safety Senses will be shocked Exposure to blood and other biological materials Inoculations against Hepatitis B Wear latex gloves Protective shoe covers Liquid repellent coveralls Particle mask/respirator, goggles, or face shield

24 Be alert to sharp objects, knives, hypodermic syringes, razor blades, etc Red biohazard bag Disinfect/decontaminate Eating, drinking, smoking, and the application of makeup are prohibited “Infectious Linen” laundered at the expense of the employer

25 CRIME SCENE RECONSTRUCTION Stages  Data collection  Hypothesis formation  Examination, testing and analysis  Determination of the significance of the evidence  Theory formulation

26 Legal Considerations at the Crime Scene Evidence may become excluded b/c of an “unreasonable” search and seizure of evidence Must abide by the Fourth Amendment “…must have probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”

27 Justifications for a warrantless search: 1.The existence of emergency circumstances 2.The need to prevent the immediate loss or destruction of evidence 3.A search of a person and property within the immediate control of the person provided it is made incident to a lawful arrest

28 4. A search made by consent of the parties involved

29 Mincey v. Arizona Court dealt with the legality of a four- day search at a homicide scene Involved a police raid on the home of Rufus Mincey, who had been suspected of dealing drugs Undercover police office forced entry into Mincey’s apartment and was killed in a scuffle that ensued

30 Without a search warrant, police spent four days searching the apartment They recovered bullets, drugs, and drug paraphernalia Items were introduced as evidence during trial Mincey was convicted and on appeal contended that the evidence gathered from his apartment was illegally seized

31 The court upheld Mincey’s position

32 Michigan v. Tyler A business leased by Tyler and a business partner was destroyed by fire Fire was extinguished in the early hours of the morning Fire officials and police were prevented from thoroughly examining the scene for evidence of arson

33 The building was left unattended until 8:00 am Officials returned and began an inspection of the burned premises Assorted items of evidence were recovered and removed from the building

34 On 3 other occasions---4 days, 7 days, and 25 days after the fire---investigators reentered the premises and removed additional items Each of these searches were made without warrant or without consent The evidence seized was used to convict Tyler and his partner of conspiracy to burn property and related offenses

35 The Supreme Court upheld the reversal of the conviction, holding the initial morning search to be proper but contending that evidence obtained from subsequent reentries to the scene was inadmissable.

36 Case Study: Captain Jeffrey MacDonald p. 44 Called military police in the middle of the night on Feb. 17, 1970 Said he had just regained consciousness and found his wife and two young daughters massacred in their home As the MPs arrived, they all entered the house, walking around and touching what may have proven to be evidence Many types of evidence collected, but carelessly COC poorly maintained 10 years later, Cpt. MacDonald was convicted of the murders Remains in federal prison

37 Case Study: Mark Winger An intruder named Roger Harrington bludgeoned his wife, Donnah, to death on August 23, 1995 Mark had interrupted the attack and killed Harrington The case was finally reopened and detectives, going through the files, found yet another surprise - three Polaroids taken by Officer Barringer on the night of the murders, before Donnah Winger and Roger Harrington were moved to the hospital. The photos showed the placement of the bodies, something that police say blew Winger’s version of events out of the water. In 2001, Winger was arrested. On Aug. 1, 2002 he was convicted of murder and sentenced to life in prison without the possibility of parole


Download ppt "Chapter 3: THE CRIME SCENE “ Oh, how simple it would all have been had I been here before they came like a herd of buffalo and wallowed all over it.” —A."

Similar presentations


Ads by Google