Staff Elimination Database
Definition
A database of DNA profiles from all laboratory personnel who have access to evidence or consumables. Any profile matching a contributor profile is checked against this database first. A match identifies contamination by a known individual rather than an unknown contributor.
- Contains
- DNA profiles of lab personnel with evidence access
- Checked
- First, against any unexpected contributor profile
- Purpose
- Identify known-source contamination
- Distinct from
- Unknown-contributor database searches
Common questions
Why is the staff elimination database checked before other databases in a mixture interpretation?+
Laboratory contamination from a known individual is the most easily explained and resolved source of an unexpected profile, so ruling it out first prevents an analyst from over-interpreting a contamination event as evidence of an unknown contributor.
Who is typically included in a staff elimination database?+
It generally covers anyone with physical access to evidence, consumables, or the analysis area, so crime scene officers, evidence technicians, and cleaning staff can all be included alongside analysts as potential contamination sources.
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