Criminal Investigation
Definition : Criminal investigation is the systematic
process of collecting, analyzing, and interpreting evidence to establish
facts related to a crime.
Objectives
·
Establish corpus delicti (proof that a crime
occurred)
·
Identify victim and offender
·
Reconstruct the sequence of events
·
Present evidence in court
UNNATURAL DEATH
Definition : Deaths occurring due to external causes
(not natural disease).
Types
·
Suicide → hanging, poisoning, drowning
·
Homicide → intentional killing
·
Accidental death → falls, burns
·
Undetermined
Key Forensic Indicators
·
Hanging → ligature mark (upward,
non-continuous)
·
Strangulation → horizontal mark, bruising
·
Drowning → froth, water in lungs,
washerwoman skin
·
Burns → ante-mortem vs post-mortem signs
CRIMINAL ASSAULTS
Definition : Intentional application of force causing
injury to another person
Types of Injuries
·
Blunt force → bruises, abrasions
·
Sharp force → incised wounds, stab wounds
·
Firearm injuries
Forensic investigation focuses on evidence collection,
including weapons, blood spatter analysis, and DNA from biological samples.
Bloodstain patterns and injury documentation link suspects to the scene via
Locard's Exchange Principle
SEXUAL OFFENCE
Definition : Crimes involving non-consensual sexual
acts
Types
·
Rape
·
Attempted rape
·
Sexual harassment
·
Child sexual abuse
Evidence
Collection
·
Biological samples → semen, saliva,
vaginal swabs
·
Clothing, bedding
·
Injuries (genital + non-genital)
POISONING
Definition : Injury or death caused by toxic
substances
Types of Poisons
·
Corrosives → acids, alkalis
·
Irritants → arsenic
·
Neurotoxins → organophosphates
·
Asphyxiants → carbon monoxide
Forensic Investigation
·
Preserve viscera (stomach, liver, kidney)
· Chemical analysis in FSL
VEHICULAR
ACCIDENTS
Definition : Injuries/deaths due to road traffic
accidents
Types
·
Pedestrian accidents
·
Vehicle-to-vehicle collision
·
Hit and run
Forensic Aspects
·
Skid marks → speed estimation
·
Vehicle damage analysis
·
Injury pattern analysis
o
Bumper injuries
o
Dashboard injuries
Evidence
·
Paint, glass fragments
·
CCTV footage
·
Breath analysis (alcohol)
|
Topic |
Key Points |
|
Unnatural Death |
Suicide, homicide, accidental |
|
Assault |
Blunt, sharp, firearm injuries |
|
Sexual Offences |
Biological evidence crucial |
|
Poisoning |
Toxicology + viscera |
|
Vehicular Accidents |
Skid marks, injury patterns |