Forensics Unit 1 Notes
Chapter 3 – The Crime Scene
Crime Scene- any place where evidence may be located and gather to help explain evidence
Modus Operandi- the characteristic method of operation of criminal; sometimes referred to as MO
I.
Preserving and Isolating the crime scene
A- Assess the crime scene and Assist the injured
D- Detain the witness
A- Arrest the perpetrator
P- Protect the crime scene- tape…
T- Take written notes
II.
III.
Observing and documenting the crime scene
a. Notes- help you remember details, TRANSIENT OR CONDITIONAL EVIDENCE!
b. Photographs and Videotape- catch things that observers miss
c. Sketches- give perspective to the photos and scale
Searching for Evidence
a. Line or Strip search- officers shoulder to shoulder and walk (large outdoor areas)
b. Grid Search-
c. Zone- house or area split into zones that are searched by individuals
d. Spiral (Wheel of Ray)-
IV.
V.
VI.
Collecting and Packaging Evidence
a. Dry
b. Airtight
c. Weapons fixed in a wood container
d. Biological items frozen
Maintaining Chain of Custody
a. Chain of custody- a written record of all people who have had possession of an item of evidence
Crime Scene Investigation requires the following:
a. Scientific method- covered
b. Locard Principle- covered
c. Logic and common sense- develop life long
d. Forensic techniques- learning about the rest of semester
e. Investigator collects evidence and the Forensic Scientist analyses it (not like TV)
i. Investor may ask for a particular type examination to be made with each piece of
evidence but the analyst/scientist is not strictly bound by those requests.