Do Now: Observation v. Inference
Provide 5 observations and 5 Inferences
Chapter 2Chapter 2““One chance to work a One chance to work a crime scene... ONE.”crime scene... ONE.”
Eyewitness Testimony
Faulty eyewitness testimony contributed up to 87% of wrongful convictions.
-1992 Innocence project
Observation v. Inference
Provide 5 observations
Observation v. Inference
Provide 5 observations
How information is processed in the brain
Observations Inferences Perception is limited and the way we view
Long term
memory
Short Term
memoryPerception
What WePay
Attention to
Infofrom our
senses
#2
#3.
What do you notice?
Transparency On Perception video
#4
Why can Perceptions of witnesses be faulty?
Perception is Subjective Prejudicial Emotional state
Upset/anxiety, happy or depressed
Fear at the time of stress How humans are wired
Perception test video
http://www.youtube.com/watch?v=udxOFMU46Lc&safety_mode=true&persist_safety_mode=1&safe=active
http://www.youtube.com/watch?NR=1&v=tDObotwpOPQ&safety_mode=true&persist_safety_mode=1&safe=active
Perception test video
http://www.youtube.com/watch?NR=1&v=tDObotwpOPQ&safety_mode=true&persist_safety_mode=1&safe=active
Ugly to beauty video
http://www.youtube.com/watch?v=dAnRQncZ_uk&NR=1&safety_mode=true&persist_safety_mode=1&safe=active
How to be a good observer We know that we:
1. NOT inclined to pay attention to details Make a conscious effort to examine
systematically
2. Filter out unimportant material Instead cat like data gathering machines
3. Jump to conclusions We must make observations
4. Memories are faulty Documentation is paramount,
Narrative, Photographs, Sketches
4.
A. Processing the Crime scene:-What is a Crime Scene?
• All areas over which the victim, criminal and eyewitness move during the commission of a crime.
• Pathways to and from.
• The physical location at which an offense was committed; to include lines of approach and flight.
• The area of the crime scene can be relatively small or very large.
Events while approaching the scene
Securing and preserving the scene Search and collection
What is the ultimate goal of the CSI team?
The goal of an investigator is to:1. Recognize2. Document3. Collect evidence at the scene of a
crime
Remember Locard’s Exchange Principle?
It is impossible for a perpetrator to commit a crime without leaving or taking something at or from the scene of a crime.
The Seven S’s of crime-scene investigation
1. Securing the scene
2. Separating the witnesses
3. Scanning the scene
4. Seeing the scene
5. Sketching the scene, (documenting)
6. Searching for evidence
7. Securing & Collecting evidence
Kurt Cobain
Facts about Kurt Cobain's death Found April 8th 1994 dead in his home in
Seattle Washington on the second story of his garage (green house)
Shotgun wound to the head. face was still intact contrary to popular belief 3 times the lethal dose of heroin in his blood stream no finger prints on the gun, suicide note, or shell
casing [as if they had bin wiped clean]
TheCrimeScene
Tom Grant's sketch of the scene
Objective: Identify The Seven S’s of crime-scene investigation found within your narrative
1. Securing the scene
2. Separating the witnesses
3. Scanning the scene
4. Seeing the scene
5. Sketching the scene
6. Searching for evidence
7. Securing & Collecting evidence
Anything wrong in the excerpt from the Follow Up Report?
Obvious trauma to his head. There is a Remington m-11 20 gauge shotgun between the victim’s legs with the barrel pointed towards his head and his left hand wrapped around the barrel. The shotgun is inverted with the trigger and magazine trap door pointing up. The barrel end is just above his beltline. There is a sent 20 gauge shell casing on top of a brown corduroy jacket which is on top of a beige nylon shotgun case. These are just to the left of the victim and under one of the stainless steel garden trays.
Excerpt from the Follow Up Report
Remington m-11 20 gauge shotgun
The inverted shotgun distinguishing the orientation that relates to the scene diagram
Total length 45 in
Greenhouse door
Inside the Greenhouse
The stool police claim Kurt used to "barricade" himself in the room
greenhouse lock used to back up the story that Kurt "barricaded" himself in the Greenhouse
Suicide Note
IMMEDIATE AND/OR MAJOR GOALS (OBJECTIVES)
Collection of physical evidence -record Chain of Custody Establish that a crime has been committed
(corpus delicti _ elements of the crime)
Reconstruction of the crime Identification / Link suspect to the crime
scene Establish probable cause
Physical Evidence
Any object that can establish a crime has been committed
can provide a link between a crime and its victim or
between a crime and it’s perpetrator Direct vs. circumstantial Physical vs. biological Class vs. Individual
Trace
Comparison:Two types of characteristics
Class characteristics: Substances can be associated with a group but
not individual source Blood types: use factors in blood These can ID suspects at a crime scene
Individual characteristics: Substances that are related at almost 100%
probability Fingerprints are 1x1060 that 2 peoples are the
same
The Crime Scene Investigation team
1. Police officers: first arrival, DA if warrant was needed
2. CSi: document the scene +collect evidence, recorders for: photograph, narrative, sketch Evidence collectors
3. Medical examiner/ coroner Detectives: interview witnesses
4. Specialists: specialized forensic specialists Entomology, serology, anthropology
Secure and Isolate the Crime Secure and Isolate the Crime SceneScene
There are three phases of crime scene management. Initial Notification and Response Securing, Searching the crime Scene and Documenting Disposition
These three phases can be identified in 16 basic steps.
Crime scene search case lawCrime scene search case law
LEGAL REQUIREMENTS:Ability to identify each item of evidenceDescribe exact location of evidenceReconstruct crime sceneMaintain chain of custodyExplain any changes that might have occurred between the collection and preservation of the evidence.
Objective: Role Responsibilities
Please assign a minimum of three Responsibilities to each member your team.
1. 1st Officer (+facilitator)
2. Recorder
3. Photographer
4. Sketch Artist
5. Narrative
6. Evidence Collectors
http://www.thebonecollector.com/home.html
“The Bone Collector”
If at anytime you feel threatened or uncomfortable, feel free to close your eyes! If you feel this approach will not work not you, you may sit in the hallway,
Absolutely ALL alone where the murder may still be!
2. Record the scene
• The opportunity to permanently record the scene in it’s original state must not be lost.
1. Photography2. Sketches3. Notes
Record the scene: Photography
• Conducted before anything else is done to the crime scene.
• Crime scene photographs can: • Refresh the memories of investigators and
witnesses • Provide powerful evidence to a jury
• Details positions and locations of evidence
• The crime scene and all physical evidence should be photographed from all angles.
• Videotaping of the crime scene is acceptable, not a replacement for 35mm
Record the scene: Photography
Cardinal Rules of Photography
1. Nothing moves until it is photographed!2. Film is cheap -- you can't take too many crime
scene photographs.
Once the scene has been photographed, the investigator will need to sketch the crime
Record the scene: Sketches
• The Four Keys to Crime Scene Sketch1. Dimension2. Distance3. Context4. Relationship Among Items of
Evidence
* Record the exact location and relationship of pieces of evidence to surroundings.
* Refresh the memory of the investigator.* Provide permanent record of conditions not
easily recorded.* Assist prosecutor, judge, and jury to
understand conditions at the crime scene.* Help in questioning suspects and witness.* Plan raids and roadblocks.* Help correlate testimony of witnesses.* Eliminate unnecessary and confusing details.
Purposes of Sketch
Record the scene: Rough Sketches
Record the scene: Final Sketches
Systematic searches
Need to be done so that no accusations of a cover up arise or overlook of evidence
Need one person in control to coordinate collection of evidence
Four main types Spiral Strip or Line Grid quadrant
Four main types
Spiral Strip or Line
Grid quadrant
Four main types
Spiral Strip or Line
Grid quadrant
Mobile crime scene laboratories
Protect the scene, photograph, evidence collection and packaging, latent fingerprinting.
Microscopic or Undetectable at the scene Ex. Hair, blood, fibers from clothes, Fabric
impressions, traces of paint
DO NOT carry out the functions of a chemical lab Crime scene search vehicles
Vacuum Sweeping
Critical areas of a crime scenes should be vacuumed and swept.*Looking for
traces evidence.
Collect and Package Physical Evidence Crime scene safety ALWAYS a concern!
Hepatitis, HIV, AIDS, Bio-hazardous pathogens Use forceps, doubled gloves, tyvek or kleengard
type suits NOTHING IS MORE IMPORTANT THEN:
The chain of custody A record denoting the location of the evidence
Maintain Chain of Custody
A list of all persons who came into possession of an item of evidence. List provides:
DateLocation of evidenceId # Collectors initialsPersons who handled or examined
Collect and Package Physical Evidence
Must be handled and processed in a way that prevents ANY change, between the time it is removed and the time it is received by the crime scene lab. Contamination, breakage, evaporation,
scratching, bending, LOSS Evidence should be collected intact
Collect and Package Physical Evidence
Must be organized: Packaged separately in:
Plastic pill bottlesManila envelopes Screw top glass vialsCardboard
Mailing envelopes not recommended
•Please have ready your Please have ready your crime scene reportscrime scene reports
Obtain Standards/Reference Samples
Standards/reference: Physical evidence whose origin is known, blood, hair, DNA
Buccal Swab: swab of inner portion of cheek, for cheek cells DNA profile or blood
Substrate Control: uncontaminated surface material close to an area where physical evidence has been deposited.
Obtain Standards/Reference Samples
DNA profile
Crime Scene Admissibility
Michigan v. CliffordMichigan v. TylerMincey v. Arizona
Crime Scene Admissibility
Michigan v. Clifford -Investigators searched an arson fire scene five hours after the fire was put out, withoutconsent or warrant. Incriminating evidence was recovered and used in the conviction.The US Supreme Court reversed the decision citing the need for a warrant five hoursafter the fire was put out.
Crime Scene Admissibility
Michigan v. Tyler -Arson investigators conducted three separate searches of a fire scene. The first was oneand one-half hours after the fire, but dense smoke caused the search to wait until fourhours later (the second search). The third search was weeks later. Evidence from the firsttwo searches was held admissible, but evidence from the third search was excluded.
Crime Scene Admissibility Mincey v. Arizona – investigating the shooting death of an undercover police officer in the residence of the suspect. * The police established a crime scene, conducted a thorough search of the scene and found evidence of other crimes. ** The police charged the suspect with those crimes as well and the court rejected it. *** The court recognized the need of the police to control the situation upon their arrival, and the need to establish a crime scene. But as soon as there was no more danger of evidence loss, removal or destruction, there was ample time to obtain a search warrant, particularly when evidence of other crimes was inadvertently discovered.
What is a Crime Scene?
What is a Crime Scene?
What is a Crime Scene?
What is a Crime Scene?
Lack of evidence IS evidence. •No scratches on the arms, defense wounds, could be evidence of suicide. •Must prove intent, to prove suicide.
WHAT HAPPENED HERE?
Pictures pagePictures page
Major stages in crime scene processing, (Initial and response)
1) Receive call and make initial response
2) Make careful approach to crime some
3) Establish control/jurisdiction
Major stages in crime scene processing, (Initial and response)
1) Receive call and make initial response
2) Make careful approach to crime some
3) Establish control/jurisdiction
16 STEPS (Secure, Document and Search)
4) Secure and protect, 1st officer
5) Establish/confirm crime scene perimeter, 5) Establish/confirm crime scene perimeter, assisted by multiple officersassisted by multiple officers
6) Conduct preliminary survey6) Conduct preliminary survey
7) Write narrative description
8) Photograph crime scene
9) Sketch crime scene
6) Conduct preliminary survey**6) Conduct preliminary survey**
First responding investigator should note: Who made the notification? What time did the 1st officer arrive How long did that take? “arrival lag” Weather conditions, visibility Persons on scene, at, left, or passed through Who facts ascertained by first officers Observations of “key items of evidence” Takes responsibility form officers from the scene
16 STEPS (Secure, Document and Search)
10) Evaluate for latent impressions
11) Evaluate physical evidence
12) Conduct detailed examination
13) Collect, record, mark, and preserve evidence
14) Conduct final survey of scene
15) Review documentation and process
16 STEPS IN CRIME SCENE PROCESS, (disposition)
16) Release and/or secure the scene