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Flashcards in Exam 3 Physical Evidence Deck (13):

EPO 1 name 3 Types of Evidence

Testimonial- Statement of a witness in court, usually under oath and offered as evidence of stated truth

Documentary- Evidence in written rather than oral form. Document with writing on it. Admissibility depends upon proof of the authenticity and purpose for which it is being offered in evidence

Physical- Real Evidence, evidence in the form of material objects (weapons, tools, fingerprints etc). More reliable than eye witness. Helps reconstruct the crime scene. Helps establish elements of crime and establish the ID of persons associated with the crime.
*Trace Evidence
*Impression Evidence


EPO 2 Identify the proper methods of evidence documentation

Golden Rule: Do not touch, move or alter anything until the scene is secured.
-Notes: use ink, legible, kept by each officer, accurate, chronological, general description of the scene
*Purpose is to brief others, write reports, refresh memory
*Have your name, date and start time, case number, location
-------Photos: Provide court with visual representation of scene
*Must be fair and accurate
*Create a photo log (Pic #, subject matter, location taken)
*Overall (establish location)/Intermediate Range (Relationship between items)/Close-Up (particular details of particular object)

Sketches: Two dimensional permanent record of distances, items and conditions.
---------Relevant items are on the sketch
Put evidence depicted in sketch on side number/description. Sketch will have number corresponding to evidence in drawing (usually on separate sheet of paper). Must match evidence log
Methods are baseline, rectangular coordinate and Triangulation
-------------Must remain consistent through all three methods


EPO 3 Identify the proper methods to locate, collect and package evidence

Basic Stages are
-Legal standing to be there
-Create evidence teams
-Team Leader, Photogapher, Sketch Preparer, Evidence Custodian, Specialists
*Approach to the scene
-Secure and Protect the Scene (Officer Safety most important)
-Initiate Preliminary Survey of the Scene
-Locate, identify, protect fragile evidence
-Evaluate all evidence possibilities
*Basic premises
-One chance to work the scene
-Cautious first search
-Vigorous follow-up search (Less visible/hidden evidence)

Photo in place
Mark on sketch
Note on evidence log
Two people should see evidence and observe recovery
Protect from change, collect fragile evidence first
Wear Gloves
Mark Item
Air dry wet clothing/Bloody clothing never goes in plastic

When you are done with collection do a final survey, double check documentation, all evidence is properly bagged, tagged and accounted for. Photo scene showing final condition


EPO 4 Identify the process for establishing and maintaining a chain of custody

Form is essential in the admissibility of evidence into the legal system
Life history of the item
Limit persons involved
Record chain of custody information at every stage of evidence handling or transfer from one person to another and document reason for the transfer


EPO 6 Identify the components of documents and the information available from each of these components

Letter of Transmittal
*used to request specific laboratory examinations of each piece
-provides basic facts of case
-people involved
-list of items submitted
-request of service


EPO 7 Identify the methods of obtaining admissible and useful request and non-request exemplars

-handwriting is non testimonial evidence 5th & 6th Amen offer no protection
-Disadvantage sus may try to disguise their handwriting
-use the same text -dont allow the person to see the documents
-get a personal history sheet free of disguise, most natural, sign and date both sides of exemplars/ NON REPEST EX-free of disguise
-Machines- due to wear, maintenance seize machines
-Photocopy leave trash marks


Other Info

Criminal Investigation is the systematic collection of information for identifying, apprehending and convicting suspected offenders.

Problems with Physical evidence are human error. Human Error to locate, collect, package, preserve and interpret can diminish its value to your investigation

Principle of Interchange: Every contact leaves a trace
Evidence Triangle: Suspect-->Scene-->Victim


Conducting Searches

Not a random or selective "looking"
Document what you find and DON'T find
Lane Search (fields, yards)
Grid Search (Similar to line search, same locations)
Zone or Sector (indoors)
Spiral Search (underwater)


Evidence Collection

Electronic Evidence- Computers
On, leave it on
Off, leave it off
Remove from outside sources

Friction Ridge Impressions
*Palm Prints
*Barefoot Impressions
3 Basic types
-True (Invisible latent) rest ON non-porous surfaces, rest IN porous surfaces
-Patent (visible) impressions



Collecting Evidence
*Collect Fragile Evidence First
Order for Packaging Evidence
*Document Evidence
*Mark Evidence Container
*Place evidence inside
*Seal Container
Should you mark the item of evidence?
*Only if necessary and commanded by policy

Wet Evidence
*Air dry
Place beneath drying evidence?
*Clean paper
Clothes hanger made of?
Protect from?
*Heat and Humidity
Pack In?
*Porous Container
May Package in Non-Porous Under what Conditions?
*Short period of time (2 hours) to transport if necessary



Chain of Custody
*Life history of item from time of discovery until no longer needed
*Everyone taking POSSESSION of evidence must be on chain of custody

Letter of Transmittal
*Informs the lab of what you want done with the evidence
*Includes brief synopsis of the case
*Is sent in duplicate (one letter inside package, one outside package)

Types of Evidence
*Testimonial (eye witness)
*Documentary (written)
*Physical (Real Evidence, material objects)
*Locards Theory of Interchange...no one can enter an environment without leaving some trace of his or her presence and without carrying away some trace of that environment.



Proper Methods of Evidence Documentation
-Overalls/Intermediate/Close up 2 Times
Record most amount of information, true and accurate representation of the scene
-Methods are baseline, rectangular coordinate and Triangulation
2 or more people for measurements
-Rough sketch "not to scale" corrections must be made at scene

Class Characteristics
Qualities shared by all members ex Nike shoes, ford pick-up
Individual Characteristics
Properties of evidence that can be associated with a common source with an extremely high degree of certainty.
Even among members of same class demonstrates uniqueness or individuality ex fingerprints, tire tracks, foot impressions made by worn tires or shoes


EPO 5 Identify the procedure for requesting laboratory analysis of evidence

call the unit for specific instructions, or LETTER OF TRANSMITTAL
-INCLUDE Inv name, agency, add, phone #, and case identifiers
-provide lab with brief description of nature of facts of he case, list of all items submitted
-state what type of exams you want to be performed and where the report to be sent

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