Jan 15, 2014
C RIME S CENE M ANAGEMENT &P HY . E VIDENCE
Locard’s Principle: scientist Edmond Locard, 18771966.
“Every contact leaves a trace… and takes a trace with it.”
Physical Evidence: Any item that may yield positive proof of the guilt or innocence of a person with respect to a specific crime or
C AN BE :
Circumstantial: Indirect evidence doesn’t prove anything, but gives evidence of something that happened, without
declaring innocence or guilt, but helps to solidify the case.
Direct: a series of facts that yield prominent evidence. (ex. A man robbing a bank, evidence from start to finish), an
expert witness gives such type of evidence.
Testimonial: a signature, a will or document, a dying declaration, a confession; a verbal or physical statement
declared in front of a lawyer, verified by the lawyer’s presence.
Forensic: fingerprints, DNA profile identified to a person of interest, and evidence directly attributed to a suspect
specifically by process.
M UST BE:
Relevant: relate directly to the case, must assist to prove a fact or issue, can be introduced to prove previous
involvement or convictions (no previous convictions may be pulled into a current case).
Reliable: who is reliable?, questionable truths, safeguards? And who determines if a witness is reliable or not?, you
have to be sworn in (on a bible or to the judge, a child is asked blatantly). An eye witness may be emotionally invested
in a case or suspect, which leads to questionable eye witness evidence
C OLLECTION OF PHYSICAL EVIDENCE
1. Connect accused to the crime, crime scene or victim
2. Danger of relying on eye witnesses to prove case
3. Difficulty of statement/confession admissibility
Assists Investigators: to prove beyond a reasonable doubt
Supporting or confirming the facts upon which a reasonable and strong suspicion is based (aka: a gut feeling)
It helps to establish the case for or against the suspect
Basic investigative leads and clues Strengthen one or more weak positions in the chain of evidence
Support the accuracy of statements made by witness or impeach false or improper statements
F OUR M AIN ISSUES
1. Legally Obtained: search warrant, Police can enter under a coroner’s authority,
2. Properly Identified: victim or murder weapon, must be documented visually, video, photos, drawings, seizing
3. Proper Handling and Continuity: prove that it is in fact the murder weapon, and potentially the suspect,
without contamination, without letting it ‘sweat’ in its package, sealed packages, keeping track of the chain of custody
4. Material and Relevant: exhibit clearly to a time and place,, discriminative, significant in the context of the crime?
C OLLECTION AND P ACKAGING
Gloves and suits
Minimum access and handling
Recorded (exhibit registry or log)
Rubber gloves, lots
Biological protection suits
Paper bags, plastic bags, containers
So that we can:
Yield further information
Require specialized equipment
Pay for analysis
Procedure ruining the evidence?
P ROOF P OSITIVE
Does the evidence provide us with the positive