Comprehensive Review in Crime Detection and Investigation

FUNDAMENTALS OF CRIMINAL INVESTIGATION

• Investigation Defined: A systematic study of facts concerning a crime. Derived from the Latin term investigare, meaning to trace or locate. Its primary modern objective is to locate the suspect, currently termed a Person of Interest (POI).

• Crime Investigation: The act of gathering facts regarding the commission of a crime.

• Criminal Investigation Detail:

  • Defined as an art dealing with the identity, location, and apprehension of a person who commits a crime and providing evidence of guilt in criminal proceedings.

  • It is a systematic process of identifying, collecting, preserving, and evaluating information for the purpose of bringing a criminal offender to justice.

  • It involves the collection and analysis of facts concerning persons, things, and places to identify the guilty party and provide admissible evidence.

  • The primary goal is gathering factual information based on a systematic plan, proceeding in an orderly and logical manner.

• Crime Investigation Report: A written statement of facts relevant to the case.

• Chain of Custody: The unbroken transfer of evidence. It ensures that items collected at the crime scene are the same items presented in court, tracking from creation to disposal.

• Physical Evidence:

  • Any substance or object found at the crime scene.

  • Known as the "unimpeachable witness" because it does not lie, lacks bias, and is considered the highest order of evidence.

  • It aids in establishing that a crime occurred; unlike human witnesses who may lie or documents that may be altered.

• Kinds of Physical Evidence:

  • Corpus Delicti: The "body of the crime"; evidence proving a crime actually exists.

  • Associative Evidence: Evidence that links a suspect to the crime (e.g., a wallet or clothing found at the scene).

  • Tracing Evidence: Evidence used to locate a suspect (e.g., fingerprints ($FP$), blood, or saliva).

• Types of Physical Evidence Examination:

  • Physical Examination: Use of human senses to examine evidence.

  • Scientific Examination: Use of scientific instruments for analysis.

• Six ($6$) Cardinal Points of Criminal Investigation (Kipling Method):

  • What question

  • Who question

  • When question

  • Where question

  • Why question

  • How question

• Principles of Investigation:

  • No two crimes are alike.

  • The law provides the elements of what happened.

  • Perpetrators always make mistakes.

  • Evidence is always present.

  • People always lie to the investigator.

  • Learn to work with others; public opinion is important.

  • There is never enough time; think like a "native," not a criminal.

  • Document everything and establish credibility in court.

• Criminal Investigation vs. Criminalistics: Criminal Investigation deals with the collection and preservation of physical evidence, whereas Criminalistics deals with the scientific study of that evidence.

• Criminal Identification Types:

  • Positive Identification: Uses information identified beyond question and is legally accepted (e.g., fingerprints).

  • Tracing Identification: Involves use of information indicative of personal identity.

• Techniques of Criminal Identification:

  • Dactylography: The scientific examination of fingerprints for identification.

  • Rogues Gallery: Use of photographic files (mugshots) where witnesses examine photos of known criminals at police stations.

  • General Photograph: Showing facial types not necessarily representing the criminal but including features like baldness, nose shape, ear size, chin formation, or cartographic sketching.

  • Police Line-up: Letting a witness select a suspect from a group of individuals.

• Three Tools of Investigation:

  • Interview: Questioning witnesses.

  • Interrogation: Questioning suspects.

  • Instrumentation: Use of criminalistic science.

• The Four ($4$) I’s of Investigation: Interview, Interrogation, Instrumentation, and Information (Information is considered the "bloodlife" or "bloodline" of investigation).

• Traditional Sources of Information (James N. Gilbert): Human sources, Documentary sources, Physical sources, and Informants/Informers.

  • Informant: One who voluntarily provides information and offers to be a witness.

  • Informer: A professional informant, usually a recruited or paid asset.

CRIME SCENE PROCEDURES AND PHOTOGRAPHY

• Four ($4$) Kinds of Photographic Views:

  • General View: Over-all view of the crime scene from all angles.

  • Medium View: Crime scene divided into zones or grids.

  • Close-up View: Focus on specific physical evidence.

  • Extreme Close-up: Focus on minute details of evidence (microphotography).

• Photographic Distances:

  • Long-range: Distance from doorway to the room and corners.

  • Mid-range: $6$ to $8$ feet from the items being photographed.

  • Close-up: $1$ to $5$ feet from the object.

• MAC Principle: Never Move, Alter, or Cut any physical evidence unless it has been photographed, sketched, and measured.

• Initial Actions and Priorities:

  • Bring the victim to the nearest hospital (First thing to be done).

  • Clear the area (First thing in a suicide or holp-up situation).

  • Cordon the area (First thing to preserve the crime scene).

  • Photograph the scene (First thing in an accident scene).

• Searching Methods for Evidence:

  • Strip Method: Walking in a straight line across the area, then returning to the start side.

  • Double Strip (Grid) Method: More thorough; provides a second look from a different angle.

  • Spiral Method: Starting at a center point and working outward in a clockwise manner.

  • Wheel Method: Searching in spokes from a center.

  • Zone or Quadrant Method: Dividing the area into four smaller squares, assigning an officer to each.

• Scene of Crime Operation (SOCO):

  • Applies to: Murder, Homicide, Rape with Homicide, Arson, Robbery with Homicide, and heinous/sensational cases.

  • SOCO Team Composition: Team Leader, Driver/Evidence Custodian, SOCO Specialists/Technicians, Health Officer, Crime Photographer, Sketcher/Measurer, and Forensic Chemical Officer.

• Crime Scene Sketches:

  • Used to refresh the investigator's memory and show exact locations/relationships of objects.

  • Sketch in Locality: Shows the scene and environs (neighboring buildings, roads).

  • Sketch of the Ground: Shows the scene with nearest surroundings (house with garden).

  • Sketch of Details: Describes the immediate scene only (the specific room).

  • Cross Projection: Pictures the floors, walls, and ceilings simultaneously.

  • Rough Sketch: Informal sketch made at the scene.

  • Finished Sketch: Carefully drawn and labeled sketch made at the office.

INTERVIEW AND INTERROGATION TECHNIQUES

• Interview vs. Interrogation:

  • Interview: Questioning a person believed to have knowledge of official interest to the investigator.

  • Interrogation: Vigorous or aggressive questioning of a suspect or a reluctant witness to elicit a full disclosure of information.

• Format of Interview (IRONIC Acronym):

  • I - Identity: Investigator identifies themselves by name, rank, and agency.

  • R - Rapport: Establishing a good relationship with the witness.

  • O - Opening Statement: Explaining why the witness is being contacted.

  • N - Narration: Allowing the witness to tell their story without interruption.

  • I - Inquiry: Making clarifying inquiries after the narration.

  • C - Conclusion: Ending the interview once information is exhausted.

• Types of Interview:

  • Background Interview: Obtaining personal data (simplest type).

  • Subjective Interview: Questions phrased based on the subject's perspective.

  • Objective Interview: Acquiring specific data/facts regarding a case (answers the $6$ cardinal points).

• Stages of Interrogation Session:

  • Initial Stage, Focusing Stage, and Concluding Stage.

• Interrogation Techniques:

  • Emotional Appeal: Using emotional stimuli to prompt the subject to confide.

  • Sympathetic Approach: Exploiting the suspect's need for sympathy.

  • Shifting the Blame: Suggesting the suspect is not the type of person to commit such a crime.

  • Mutt and Jeff: Two agents: Mutt is relentless and cold; Jeff is kind-hearted.

  • Bluff Sphere Technique: Using deception to encourage a confession.

• Legal Requirements (Art III, Sec. 12 (1) 1987 Philippine Constitution):

  • Right to remain silent.

  • Right to competent and independent counsel, preferably of own choice.

  • If unable to afford counsel, one must be provided.

  • Prohibition of torture, force, violence, threat, intimidation, secret detention, or incommunicado status.

  • Confessions obtained in violation are inadmissible.

GATHERING AND SAFEKEEPING OF PHYSICAL EVIDENCE

• Categories of Evidence:

  • Movable/Removable: Can be picked up and transported.

  • Fixed/Immovable: Cannot be easily moved due to size/shape.

  • Fragile: Requires special care to prevent deterioration.

• Blood Evidence Procedure:

  • Photograph blood spatters before collection.

  • Air dry materials on clean paper before bagging.

  • Use paper bags; do not fold across the stained area.

  • Comparison Standard: Take $5cc$ of blood each from victim and suspect in separate vials.

• Saliva Evidence:

  • Air dry on paper, then place in a paper bag.

  • Comparison Standard: Cotton swabs from victim and suspect mouths, dried and packed in paper envelopes.

• Glass Evidence:

  • Dust for fingerprints if from a Molotov cocktail.

  • Pack in fastenable metal cans.

  • Use tweezers to avoid scratching edges.

  • Standard for comparison: Sample at least the size of a one-peso coin from the point of impact.

• Explosive Debris:

  • Get debris from the blast focus and material up to $3$ to $5$ inches deep.

  • Store in clean, unused metal cans.

• Firearms and Ammunition:

  • Do not insert anything into the barrel.

  • Pick up by the trigger guard or checkered grip.

  • Unload but do not wipe or clean.

  • Gunshot Residue ($GSR$): Swab back of hands and palms with $5\%$ nitric acid. Do not collect if over $6$ hours have passed or if a $.22$ caliber was used.

  • Mark bullets on the base; mark cartridge cases inside or near the mouth.

• Fingerprint Gathering:

  • Absorbent Materials: Place in a plastic bag; wear light cloth gloves.

  • Hard Objects: Photograph plainly visible latents before development. Brush powder in a swirling motion.

  • Lifting Tape: Place tape about $\frac{1}{2}$ inch in front of the print and slide thumb over it.

  • Skin: Collect immediately using dusting or electronic techniques; do not wash the skin first.

• Food and Drug Specimens:

  • Liquids: Minimum of one pint in a leak-proof container.

  • Plant Materials: Air dry on brown paper for $24$ hours, then place in a pillbox.

  • General Rule: Do not mix specimens in a single bag.

SPECIAL CRIME INVESTIGATION: HOMICIDE AND MAJOR CRIMES

• Homicide Investigation (Article 249 RPC): Investigation of the killing of another without specific circumstances like parricide or murder.

• Autopsy (Necropsy): Postmortem examination of a dead body and its organs to determine the cause of death and sequence of changes. Performed by a pathologist.

• Estimation of Time of Death:

  • Cessation of breathing and pulse; loss of muscle tone in eyeballs.

  • Body Temperature: Life temperature is $98^{\circ}F$. If cold/clammy, death occurred at least $18$ to $24$ hours prior.

  • Postmortem Lividity: Purplish discoloration on parts nearest the floor. Begins $1$ to $2$ hours after death.

  • Rigor Mortis: Stiffening of muscles. Starts in face/jaws $3$ to $5$ hours after death; involves entire body in $8$ to $12$ hours; remains for $12$ to $20$ hours.

  • Cadaveric Spasm: Immediate stiffening of hands/arms at the moment of death.

  • Stomach Contents: Stomach is usually empty $4$ to $6$ hours after the last meal.

• Gunshot Wounds:

  • Entry Wounds: Neat round holes with a gray ring and small blood quantity.

  • Exit Wounds: Larger, ragged, torn, with significant blood escape.

  • Contact Wound: Dirty appearance, larger diameter than a bullet, charring of tissues from heat.

  • Distances ($2$ to $18$ inches): Show smudging (smoke/soot) and tattooing (unburned powder/metal particles).

• Asphyxia: State of collapse due to oxygen deficiency. Includes smothering, hanging, and strangulation.

• Drowning Characteristics: White foam from nose/mouth; objects clutched in hands; mouth usually open.

• Robbery (Article 293 RPC): Taking personal property with intent to gain, using violence, intimidation, or force upon things.

• Kidnapping (Article 267 RPC): Private individuals depriving another of liberty. Elements include duration over $5$ days, simulating public authority, or serious injuries.

• Rape (RA 8353 - Anti-Rape Law of 1997): Committed through force, threat, or fraudulent machinations; if the party is under $12$ years of age or demented; or by sexual assault via other orifices.

DRUG EDUCATION AND VICE CONTROL

• Drug Defined: A chemical substance that brings about physical, physiological, or psychological change.

• Narcotics: Drugs that produce sleep or stupor and relieve pain, depressing the Central Nervous System ($CNS$).

• Psychotropic Substances: Drugs with affinity for or effect on the psyche.

• Cannabis (Marijuana): Principal ingredient is Tetrahydrocannabinol ($Delta-THC$). In small amounts, it acts as a depressant; in large doses, a hallucinogen.

• Opium Derivatives:

  • Morphine: Principal alkaloid of opium.

  • Heroin: Semi-synthetic opiate synthesized from morphine. Black tar heroin has $60$ to $70\%$ purity.

• Synthetic Narcotics: Potent analgesics like Methadone, Pethidine, and Fentanyl (up to hundreds of times more potent than morphine).

• Cocaine: Alkaloid from the coca bush (Erythroxylon). Crack is the freebase form obtained by heating cocaine hydrochloride with baking soda/ammonia.

• Sedatives/Hypnotics:

  • Barbiturates: Central nervous system depressants (e.g., yellow jackets).

  • Benzodiazepines: Valium (Diazepam), Rohypnol (Flunitrazepam).

• Hallucinogens: D-Lysergide ($LSD-25$), Phencyclidine ($PCP$), Mescaline (Peyote cactus), and Psilocybin (magic mushrooms).

• Classification under Republic Act 9165 (Comprehensive Dangerous Drugs Act of 2002): Provides a single definition for "dangerous drugs," removing distinctions between prohibited and regulated drugs.

• Methods of Drug Administration:

  • Oral Ingestion: Passes through the stomach.

  • Inhalation: Gaseous form enters lungs.

  • Injection: Subcutaneous (skin popping), Intramuscular, or Intravenous (most rapid).

  • Snorting: Inhaling powder through nasal coats.

  • Buccal: Placing drug under the lips.

  • Suppositories: Vagina or rectum.

• Drug Testing Phases:

  • Screening Test (Color Test): Preliminary, non-specific.

    • Cannabis: Duquenois-Levin = violet.

    • Cocaine: Cobalt Thiocyanate = blue.

    • Methamphetamine ($Shabu$): Marquis test = orange to brown; Simon test = blue.

  • Confirmatory Test: Uses Gas Chromatography or Mass Spectrometry to validate screening results. Must be challenged within $15$ days.

• Penalties for Illegal Use (Sec 15 RA 9165):

  • First offense: Minimum of $6$ months rehabilitation.

  • Second offense: $6$ years and $1$ day to $12$ years imprisonment and a fine of $P50,000$ to $P200,000$.

TRAFFIC MANAGEMENT AND ACCIDENT INVESTIGATION

• History and Ancient Modes:

  • Man Power: Carrying poles, Sledge on rollers.

  • Wind Power: Chinese Kite, Da Vinci’s Ornithopter, Montgolfier Balloon ($1782$).

• Types of Roads: Highways (high-speed), Urban Streets (access to property), and Rural Streets (local/collector).

• Traffic Management Scope: All public surface facilities, parking, agencies for planning/funding, and enforcement for licensing.

• Agencies Involved: DOTC (Land Transportation Office), DPWH, PNP-Traffic Management Group ($TMG$), and Courts.

• Five Pillars of Traffic: Engineering, Education, Enforcement, Ecology (Environment), and Economy.

• Important Provisions of RA 4136 (Land Transportation Code):

  • Motor Vehicle: Propelled by power other than muscular (excluding road rollers, bulldozers, etc., not used on public highways).

  • Professional Driver: Hired to operate a vehicle for private or public use.

  • Parking: Stopping on the shoulder or edge of a highway and remaining inactive.

• Driver's License Types:

  • International ($90$ days limit), Military, Professional, Non-Professional, and Student Permit.

  • Restrictions: $1$ (Motorcycle), $2$ (Vehicle up to $4500\,kg GVW$), $6$ (Articulated up to $1600\,kg$).

• Speed Limits (RA 4136):

  • Open country roads: $80\,km/h$ (Cars), $50\,km/h$ (Trucks).

  • City/Municipal streets: $30\,km/h$.

  • Throught streets/Boulevards: $40\,km/h$.

• Plate Number Color Coding:

  • Green on White: Private.

  • Black on Yellow: Public Utility.

  • Red on White: Government.

  • Blue on White: Diplomatic.

• Registration Schedule (Last Digit of Plate):

  • 1 (January), 2 (February), … 0 (October).

• Traffic Signs and Markings:

  • Danger Warning: Triangle with red borders.

  • Regulatory: Impose legal restrictions.

  • Informative: Rectangular blue/white.

  • Double Yellow Line: Absolutely no overtaking.

  • Single White Dotted Line: Overtaking possible if clear.

• Accidents:

  • Types: Property Damage, Slight, Less Serious, Serious, Fatal.

  • Skidmarks: Marks caused by locked wheels due to sudden braking.

  • Legal Liabilities: Culpa Contractual (contractual negligence), Culpa Aquiliana (civil tort), Culpa Criminal (negligence resulting in crime).

FIRE BEHAVIOR AND INVESTIGATION

• Theories of Combustion:

  • Fire Triangle: Fuel, Heat, Oxygen (in equal proportion).

  • Fire Tetrahedron: Fuel, Oxygen, Heat, and Chemical Chain Reaction.

  • Life Cycle of Fire: Input heat, Fuel, Oxygen, Proportioning, Mixing, Ignition, Continuity.

• Elements of Fire:

  • Heat: Measure of temperature in degrees.

  • Oxygen: Supports fire at approximately $21\%$ of air volume.

  • Fuel: Combustible substance (Solid, Liquid, or Gas).

• Definitions:

  • Pyrolysis: Thermal decomposition of solid fuel through heat action.

  • Endothermic Reaction: Energy is absorbed/added.

  • Exothermic Reaction: Energy is released/given off.

  • Flashover: Entire surface of a room sweeps with flames due to heat.

  • Backdraft: Smoke explosion from sudden oxygen introduction.

  • Conflagration: Large fire destroying a municipality’s function.

• Products of Combustion: Fire gases, Flame (luminous body), Heat, and Smoke.

• Heat Transmission:

  • Conduction: Through an object.

  • Radiation: Discharge through air/space.

  • Convection: Moving currents of liquid or gas.

  • Direct Contact: Spread by flame contact.

• Fire Extinguishment Methods: Cooling (removing heat), Smothering (removing oxygen), Separation (removing fuel), and Chemical Interruption.

• Classes of Fire:

  • Class A: Flammable solids (wood, paper).

  • Class B: Flammable liquids/gases.

  • Class C: Electrical fire.

  • Class D: Combustible metals (Magnesium, Lithium, Uranium).

  • Class K: Kitchen fires (grease/oils).

• Vapor Density Examples:

  • Hydrogen: $0.1$

  • Acetylene: $0.9$

  • Butane: $2.0$

  • Gasoline: $3.0$ to $4.0$

• Fire Extinguisher Mechanisms:

  • $H_{2}O$: Reduces temperature ($30$ to $40\,ft$ discharge).

  • $CO_{2}$: Displaces oxygen ($3$ to $8\,ft$ discharge).

  • Dry Chemical: Bonds oxygen ($5$ to $20\,ft$ discharge).

• Hazardous Materials Identification:

  • Class 1 (Explosives), Class 2 (Gases), Class 3 (Flammable liquids), Class 4 (Flammable solids), Class 8 (Corrosives), Class 9 (Miscellaneous).