This document discusses different types of evidence that can be used in criminal investigations and trials. It outlines that evidence must be competent, properly collected, identified, filed, saved, and have a clear chain of custody. There are many types of evidence including physical, direct, indirect, trace, prima facie, associative, corpus delicti, probative, and exculpatory evidence. When presenting evidence in court, the chain of custody from collection to presentation must be clearly documented and explained. Scientific evidence standards for admissibility were established in Frye v. US and Daubert v. Merrell Dow Pharmaceuticals.

1. CRIMINAL
INVESTIGATIONS
AND THE LAW
Chapter 5

2. Evidence
• Must be competent: Properly
-collected
-identified
-filed
-saved
-chain of custody

3. 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

4. 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

5. Evidence
• How presented:
-who are you presenting to?
-clean boxes/containers
-labeled correctly
-in order

6. 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
8.Theory falsifiable/testable
9.Peer review/published
10.Known error rate
11.Standards
12.Degree accepted by relevant scientific community