1. Essential Qualities of an Investigator
Self-Discipline
Ethical
Uses legal means and methods
Ability to win confidence of people
Good at documentation
Systematic/organized
System of contacts/informants

2. Objectives of A Criminal Investigation
To prove or disprove that a crime was committed.
To identify and locate the suspect (s)
a. By effective crime scene management
b. By eyewitness info to include the victim
c. d. By confession
3. To provide evidence of guilt
a. By physical/circumstantial evidence
b. By establishing the elements of the crime
Successful investigation
When everything was done that could, or should, be done whether the case is solved or not

3. Definitions Crime Scene:
The locale within the immediate vicinity of the occurrence wherein evidence may be found.
Evidence
Evidence consists of those things offered to prove the existence of a fact.
Crime Scene Search:
A planned, coordinated, legal search by competent persons to locate evidence and/or witnesses to the crime under investigation
Reconstruction of a crime scene is a series of individual problems that, when solved, contribute to the reconstruction of the whole event.

4. Preliminary Investigation
Three Major Functions at a Crime Scene
Recognition of Evidence
Record the location, condition, etc.
Collection, control and preservation

5. Organization of the Crime Scene
Reconstruct what happened
Determine the sequence of events
Find out what the suspect did or did not do
Establish the M.O.
Determine what property was stolen or what was left by the suspect
Reveal the motive
Locate and interview witnesses

6. Importance of the Crime Scene Search
Evidence at the scene may be the only way of placing the suspect at the scene and/or connecting them with the crime.
Attorneys will attack methods of collection, processing and handling – it must be done right!
When properly collected, identified and presented, physical evidence will stand where eye witnesses, confessions and admissions may fail.
It may help to establish Most serious/major crimes end up in court.
corpus delicti and/or modus operandi
THERE IS ONLY ONE CHANCE TO RECOVER EVIDENCE.

7. CRIME SCENE CONTROL
The actions which the first arriving officer at the crime scene takes to make sure that the integrity of the scene is maintained. Control also includes preventing people at the scene from becoming combatants and separating witnesses
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8. TYPES OF EVIDENCE Testimonial (eyewitness statements)
Documentary (records, confessions)
Physical – which includes:
3 General Categories of Evidence:
- Corpus Delicti – establishes that a crime has been committed, I.e. a body
- Associative – Links a suspect to the crime
-Trace (hair, fibers, blood)
-Direct (fingerprints, blood alcohol content)
-Circumstantial (seen leaving the scene)

9. Specific Classifications of Evidence
Hand out

10. Typical Documentation of a Major Crime Scene
Note: Most cases do not require extensive documentation. Major cases (death, sexual assault, robbery w/injuries) are more likely to have this type of documentation.
Crime Scene Entry Log
Admin Log (who is doing what)
Assignment Sheets (what I did)
Photo log
Evidence Recovery Log
Lifted-Prints Log

11. EVIDENCE RECOVERY LOG
The evidence recovery log is an important document which records all pieces of physical evidence found at a crime scene. This is critical if the case is to be successfully prosecuted later.
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12. Typical Problems at Major Crime Scenes
Weather
Mental State/Emotional Level of Victim, Witnesses and by-standers
Lack of sufficient processing equipment or manpower
Command who drop by
News media if a high profile event (murder)

13. MAJOR CONSIDERATIONS OF THE CRIME SCENE SEARCH
Boundary Determination
Choice of Search Patterns
Instruction of Personnel
Coordination
Documentation
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14. Areas Where A Search for Evidence Should be Made
Near where event occurred (near body)
Point of Entry on scene
Point of Egress from scene
Suspect (clothing, hands, fingernails)
Vehicle used
Suspect residence
The list of locations to be searched may be as extensive as the crime is complex.

15. CRIME SCENE SEARCH PATTERNS
Spiral
Strip/Line
Grid
Zone/Quadrant
Pie/Wheel
CRIME SCENE SEARCH PATTERNS
The crime scene coordinator may choose from a variety of crime scene search patterns based upon the type and size of the crime scene.
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16. COLLECTION, PRESERVATION AND CARE OF EVIDENCE CHAIN OF CUSTODY

17. DOCUMENTING THE CRIME SCENE
WAYS TO DOCUMENT A THE CRIME SCENE VISUALLY INCLUDE:
Video taping
Photographing
Sketching
(Courtesy Lewiston, Maine, Police Department)
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18. Crime Scene Sketches Relates to the sequence of events at the scene
Accurate portrayal of the physical facts
Establishes the precise location and relationship of objects and evidence at the scene
Helps create a mental picure of the scene
Provides a Permanent Record
Usually admitted in Court

19. Why Worry About the Police Report
WHO READS THE REPORT?

20. REPORT WRITING Good reports answer the following questions: WHO WHAT
WHEN
WHERE
HOW

21. REPORT WRITING TESTS OF A REPORT
IS THE REPORT COMPLETE, CONCISE, CLEAR AND ACCURATE
WILL AN ORAL EXPLANATION BE REQUIRED TO EXPLAIN WHAT IS ALREADY INCLUDED
CAN STATEMENTS MADE IN THE REPORT BE PROVEN OR DEMONSTRATED BY EVIDENCE
IS THE REPORT FREE OF BIAS

22. Main Categories of Police Reports
Complaint/Major Offense Reports
Followup/Supplmental Reports
Miscellaneous:
Evidence Reports
Lab Reports
Etc. (Depends on Agency)