Pattern Evidence
Definition
Two-dimensional or three-dimensional patterns: bloodstain spatter, glass fracture, tool marks, tyre marks, fire burn patterns, gunshot residue distribution.
- Dimensionality
- Two-dimensional (bloodstain spatter, tool marks) or three-dimensional (fracture, gunshot residue distribution)
- Examples
- Bloodstain spatter, glass fracture, tool marks, tyre marks, fire burn patterns, GSR distribution
- Analysis basis
- Shape, distribution and geometry rather than chemical composition
- Interpretation need
- Scene context and reconstruction, not the mark alone
Common questions
How does pattern evidence differ from trace evidence?+
Trace evidence is a transferred material, such as fibre or paint, identified by composition. Pattern evidence is the physical arrangement or shape an event leaves behind, and its value comes from geometry and distribution, which is why it usually needs scene documentation before it is moved or altered.
Why is bloodstain pattern analysis grouped with tool marks and fracture patterns?+
All three rely on the same underlying logic: reconstructing a mechanism (impact angle, force direction, sequence) from the residual shape left on a surface, rather than from a chemical or biological signature.
Related terms
- Chain of Custody
- The documented chronological record of who collected, handled, transferred, and examined a piece of evidence. For digital evidence, chain of custody includes...
- Class Characteristics
- Features deliberately or systematically imparted to a group of items by design or manufacture, such as the calibre of a bullet, the...
- Conditional Evidence
- Evidence whose meaning comes from the state or condition of a scene at the time of the crime, not from the physical...
- Control Sample
- A water sample collected from the suspected drowning environment at or shortly after the time of body recovery. Its diatom assemblage is...
- Form 21 (Viscera)
- Standard Indian forwarding form for viscera and biological samples sent to the FSL toxicology division, listing exhibits, preservatives, FIR number, autopsy surgeon...
- Individual Characteristics
- Surface features on a fired bullet or cartridge case that arise from random or unique events (tool wear, corrosion, service damage) and...
- Locard's Exchange Principle
- The foundational idea that every contact between two surfaces moves material in both directions, giving the forensic process its starting premise: physical...
- Physical Evidence
- Any tangible item or material that can help establish or disprove a fact relevant to a case. Distinguished from testimonial evidence by...
- Tamper-Evident Seal
- A physical barrier (tape, sticker, wax) applied to packaging that shows visible damage if the package has been opened after sealing. Courts...
- Transfer Evidence
- Material exchanged between people, objects and locations: hair, fibres, paint, glass fragments, soil, biological fluids. Direct application of Locard.
- Transient Evidence
- Evidence that changes or disappears over time regardless of investigator action: body temperature, odour, melting substances, or fleeting biological changes. Must be...