Elimination Sample
Definition
A known reference sample collected from someone who had legitimate access to a scene or item, used to separate their class and individual characteristics from those of an unknown contributor. Critical for fibres, fingerprints, and DNA.
- Source
- Known individual with legitimate access
- Purpose
- Separate known from unknown contributors
- Applies to
- Fibres, fingerprints, DNA
- Sample nature
- Reference, not questioned
Common questions
Why can't an examiner just assume trace evidence belongs to the offender without elimination samples?+
A scene routinely carries material from residents, visitors, first responders, and lab personnel, so without a reference sample from each of them an examiner cannot tell whether a matching fibre or print is evidentially significant or simply from someone with an innocent reason to be present.
How does an elimination sample differ from a suspect's reference sample?+
Both are known reference samples collected the same way, but an elimination sample is taken from someone expected to be excluded, such as a resident or officer, while a suspect sample is collected specifically to test whether that person's profile matches the unknown evidence.
Related terms
- Acquired Characteristics
- Individual characteristics that develop after manufacture through use, wear, damage, or corrosion. A new shoe has only class characteristics; a worn shoe...
- Class Characteristics
- Features deliberately or systematically imparted to a group of items by design or manufacture, such as the calibre of a bullet, the...
- Comparison Microscopy
- A technique in which known and questioned samples are viewed simultaneously through split or adjacent fields in a single instrument. Used in...
- Individual Characteristics
- Surface features on a fired bullet or cartridge case that arise from random or unique events (tool wear, corrosion, service damage) and...
- Source Attribution
- The inferential step of linking a trace to its donor. Serology identifies blood as human and potentially as a specific genetic type;...