Part 1

1.
A systematic, methodical, and detailed inquiry into the past and present
2.
Corpus Delicti – elements of a crime
3.
Act and Intent – the crime committed and with purpose
4.
Degree of crime – what charge to file
5.
Investigation must prove each element

1.
Characteristic way a criminal commits a specific crime
2.
Provide clues in both obvious and less obvious crimes
3.
They are beneficial
4.
Do not have decisiveness of past

1.
Preliminary investigation
- first officer on scene
- minor crime: investigates
- major crime: secure scene
2.
Follow-up investigation
- by detectives
- by patrol officers
- builds on what was learned
- during preliminary investigation

1.
Radio call to officer
- time of day / weather / daylight / artificial lighting
2.
Safe to enter
- suspect not at crime scene
3.
Render first aid
- show pathway to victim
- for medical professionals
- crime scene technicians
- other volunteers

4.
Protect scene
- all non-essential people
- police administrators
- the press
- family members
5.
Identify witnesses
- be sure to get I.D. from people that have information
- keep driver’s license, if necessary

1.
Locate witnesses
- eyewitness
- people who saw a possible suspect
- saw suspect vehicle
2.
Identify victim
- contact family and friends
- try to find last person who saw victim alive
3.
Check local and state files
- M.O. files / computer files / fingerprints

1.
Direct evidence
- “I saw, I heard, I smelled, I tasted” a. Includes: fingerprints / DNA / ballistics / dental comparisons / handwriting samples b. Testimony by expert witnesses
2.
Circumstantial evidence
- shoe impressions / tire tracks / types of clothing / vehicle / etc.

1.
Take into custody (probable cause)
2.
Drive-by: witness to identify
3.
Advise of rights
4.
Note “ spontaneous ” remarks
5.
Interrogation of suspect
- confession / admission / denial

1.
Search of suspect
- person / within arm’s reach
2.
Search of vehicle
- unlocked containers
- tow vehicle
3.
Search warrant
- written waiver from owner
- search warrant is best

1.
Drive-by
- victim / witness observes
2.
Photo array
- 6 to 8 photographs
- similar in appearance
3.
Line-up
- minimum: 5 / maximum: 7
- similar in build: height / weight
- facial features / hair color