Final exam study guide Flashcards
Individual evidence
Links to one unique source human/object
Locard’s principle
“Every contact leaves a trace”
And also known as trace evidence.
Physical evidence
Tangible items
Probative value
The ability to prove something that is material to a crime
Physical evidence examples
Fibers, fingerprints, glass, hair, Blood
Class evidence
Can be linked to a group of people or objects.
Primary/Secondary crime scene
Primary: the original location of CRIME or evidence.
Secondary: an alternative location where additional information may be found.
Chain of Custody
The movement and location of physical evidence from the time it is obtained until the time it is presented in court.
Packaging Evidence (Blood evidence, Fingerprints)
Each item must be collected in separate container or package and label it.
Material must not be put into an airtight bag
Presumptive test
Is an analysis of a sample which establishes either: the sample is definitely not a certain substance or the sample is probably a substance.
Confirmatory Test
Can help determine what the substance is: Limitations is that it could be wrong.
BAC
Blood alcohol content:
BAC(girl)=(0.085) ( oz)(%) / Weight
BAC(boy)=(0.071)
Find the BAC of a women who drinks three 5-ounce glasses of wine. Her weight is 135 pounds and the wince is 9% alcohol.
BAC=(0.085)(15)(9)/135
BAC=0.085 (answer)
What is the proof of a type of liquor that causes a 142 pound man to have a BAC of 0.075 after consuming six one-ounce shots?
0.075=(0.071)(6)(%) / 142
10.65=0.426X
X=25%
Double 25 and it equals 50 proof(the answer)
Positive control
Known blood will cause the color to appear (solutions are working)
Negative control
Absence of blood - no appearance of color-showing no contamination
Preciptin Test
Helps determine if it’s Human blood or animal blood