Study Unit 1
Introduction to Criminal Investigation
*Class notes are in blue.
1|Page
, © Ane Venter
The concept of Criminal Investigation Defined
○ Prevention of crime = primary function of all police organisations.
- Absolute prevention is impossible.
Note:
- When crimes are committed – police responsible for:
1. Collecting information during criminal investigation. Not all gathered information is
2. Identifying alleged perpetrators. evidence.
3. Ensuring the presence of alleged perpetrators during the
→ Information gathered is to be
court trial.
4. Submitting evidence to the court – reveal alleged assessed by an expert and
perpetrators’ unlawful actions. motivation to be admissible in
court.
○ Criminal investigation
- Multi-faceted, dynamic problem-solving endeavour.
- When arriving at the crime scene – officials must make quick decisions with limited information in a
dynamic environment.
- After criminal event is concluded – investigator is expected to:
1. Preserve the crime scene.
Conclude in forming reasonable grounds to identify &
2. Collect the information.
arrest the person / persons responsible.
3. Devise an investigative plan.
○ Def: Criminal investigation is a systematic search for the truth aimed at the positive solution of a crime.
- 2 sources of information may be available in searching for the truth:
Objective Information Subjective Information
→ Indirect source of information. → Direct source of information.
→ Factual proof / physical information in → Derived from real sensory experiences or
criminal investigation. knowledge of people, about a relevant crime
→ The literal objects. situation.
→ Weapons, bullets & bullet casings, hair, fibres, → Will prove the point in fact without
fingerprints, shoe prints, tyre marks, tool interpretation of circumstances.
impressions, bite marks, bodily fluids. → Any information that can show the court
→ Mute information / circumstantial information something occurred without need for the
/ indirect information – requires examination court to make inferences / assumptions.
and analysis by forensic experts. → Based on personal experiences.
→ Experts can demonstrate spatial relationships → Examples:
between objects, suspects, victims, timelines, 1. Eyewitness that saw it.
and criminal events. 2. Victim of crime / complaints.
→ Does not prove the offence – may contribute 3. Statement of confession from the
to a body of evidence to prove guilt beyond accused admitting to the crime / an
reasonable doubt accomplice – suspects.
→ 2 main forms: 4. People involved in the crime / aware of
1. Information transferred from crime scene the crime – but not present during the
or victim – to – perpetrator. commission of the crime.
2. Information transferred from perpetrator – 5. Informers who have information about the
to – crime scene or victim crime.
2|Page