Overview
This lecture covers the fundamentals of criminal investigation and police intelligence, focusing on definitions, processes, initial steps, tools, and types of evidence, all aligned with PRC and CHED curriculum requirements.
Fundamentals of Criminal Investigation
- Criminal investigation is the process of identifying, locating, and providing evidence against offenders.
- Three aims/phases: identify the perpetrator, locate/arrest the perpetrator, and provide evidence of guilt.
- The criminal investigator is the person responsible for these functions.
Cardinal Points of Investigation
- Six cardinal points: What (crime committed), Where (location), When (time), Who/Whom (persons involved), Why (motive), and How (modus operandi).
- Investigators must systematically answer these points to solve cases.
Qualities of a Good Investigator
- Key virtues: perseverance, intelligence, honesty, and keen observation.
Types of Criminal Investigation
- Common types: homicide, cybercrime, forensic, fraud, family and sexual violence, crimes against property, cold cases, and narcotic investigations.
Initial Steps in Criminal Investigation
- Identify and retain the reporting person for questioning.
- Identify/detain all persons at the scene and summon assistance if needed.
- Safeguard and isolate the crime scene (MAC Rule: do not Move, Alter, or Change).
- Permit only authorized personnel to enter, separate witnesses, and never touch or move objects unless necessary.
Tools of Criminal Investigation (Three I's)
- Information: acquired from open (regular), informants (cultivated), and underworld sources (grapevine); overt (open sources) and covert (closed/surveillance).
- Interview: questioning cooperative witnesses to gather information; follows IRONIC format (Identity, Rapport, Opening statement, Narration, Inquiry, Conclusion).
- Instrumentation: using scientific instruments (e.g., polygraph, microscopes) to analyze evidence.
Interview vs. Interrogation
- Interview: for cooperative witnesses, focused on obtaining information.
- Interrogation: for suspects/accused, must be voluntary (Miranda Rights apply), and employs legal techniques (emotional, sympathetic appeal, kindness, extenuation, shifting blame, Matt and Jeff, bluff on split pair, pretense of evidence, jolting).
Confession & Admission
- Confession: direct acknowledgement of guilt (extrajudicial/judicial).
- Admission: indirect acknowledgement of facts, short of guilt.
- Requirements: written, under oath, in a known language, voluntary, in presence of counsel.
Methods of Identification
- Four ways if suspect is unidentified: verbal description, rogues gallery (suspect files), general photograph (facial features), artist sketch.
- Police lineup: 7–10 persons; witness must identify independently.
Circumstantial Evidence
- Events or circumstances supporting inference of identity or guilt.
- Sufficient for conviction if there is more than one circumstance, all proven, and combined to show guilt beyond reasonable doubt.
- Elements to consider: motive, intent, opportunity.
Physical Evidence
- Types: corpus delicti (body/elements of the crime), associative evidence (links suspect to scene), tracing evidence (helps locate suspect).
- Requirements for court admissibility: proper identification, preservation, chain of custody, materiality, and relevance.
Key Terms & Definitions
- Criminal Investigator — the person in charge of investigating crimes.
- Cardinal Points — the six vital investigative questions (What, Where, When, Who, Why, How).
- Overt Information — data from open/public sources.
- Covert Information — data from secret/closed sources (e.g., surveillance).
- Interview — cooperative questioning of witnesses.
- Interrogation — questioning of suspects, must be voluntary and legally compliant.
- Confession — direct admission of guilt.
- Admission — indirect acceptance of facts related to the crime.
- Corpus Delicti — elements of the crime (“body of the crime”).
- Associative Evidence — links suspect to crime/scene.
- Tracing Evidence — items aiding in locating the criminal.
- MAC Rule — do not Move, Alter, or Change the crime scene.
Action Items / Next Steps
- Review episode 2 on crime scene investigation procedures.
- Study types, sources, and admissibility requirements for evidence.
- Practice differentiating interview vs. interrogation and their legal requirements.