CRIMINAL INVESTIGATIONS AND THE LAW

Chapter 5

Evidence• Must be competent: Properly

-collected

-identified

-filed

-saved

-chain of custody

Evidence• Types:

-Physical-anything real

-Direct-establishes proof of fact w/o other evidence’

-Indirect-tends to incriminate (circumstantial)

Trace-cannot be seen with naked eye

Prima facie-established by law

Associative-links suspect with crime

Corpus delicti-supports elements of crime

Probative-proves guilt

Exculpatory-proves innocence

Material-legitimate influence on case

Relevant-applies to matter in question

Evidence• Presenting in court:

Chain of custody:

-identify evidence found at crime scene

-document where found

-establish custody from discovery to present location

-voluntarily explain any changes occurring in evidence

Evidence• How presented:

-who are you presenting to?

-clean boxes/containers

-labeled correctly

-in order

Evidence• Frye v. US (1923):-scientific evidence

-”generally accepted by scientific community”

• Daubert v. Merrell Dow Pharmaceuticals (1993):

-federal rules of evidence apply

-trial judge gatekeepers

1.Theory falsifiable/testable

2.Peer review/published

3.Known error rate

4.Standards

5.Degree accepted by relevant scientific community