Principle of Individuality
Definition
No two objects in nature, including fingerprints, dentition and DNA profiles, are identical at sufficient resolution. Underpins every identification claim.
- Claim
- No two objects are identical at sufficient resolution
- Applies to
- Fingerprints, dentition, DNA profiles
- Role
- Underpins every individualisation claim
- Related principle
- Locard's exchange principle
Common questions
Is the principle of individuality itself scientifically proven for every evidence type?+
It is well supported for features like fingerprint minutiae and DNA profiles at sufficient marker resolution, but the strength of an individualisation claim still depends on the specific method's validated discriminating power, which varies considerably between evidence types.
How does the principle of individuality relate to a match statement in court?+
It provides the theoretical basis for saying a mark or profile could only have come from one source, but examiners still need a validated comparison method and stated error rate to translate that general principle into a specific, defensible identification in a given case.
Related terms
- Anthropometry
- The measurement of the human body for scientific purposes. In forensic history, the Bertillon system of criminal anthropometry used eleven standardised body...
- DFSS
- Directorate of Forensic Science Services, India; issues the Forensic Laboratory Manual that governs glass and soil examination procedures, including the bromoform-based density...
- Forensic Science
- The application of scientific methods and knowledge to questions that arise in legal proceedings. The goal is producing findings that are reliable,...
- 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...
- NAS 2009
- US National Academy of Sciences report that found large parts of pattern-evidence forensics had no validated scientific basis. The reference point for...