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What Every Law Enforcement Officer Should Know About DNA Evidence

Investigators and Evidence Technicians

Biological Evidence

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National Institute of Justice (NIJ) (see reuse policy).

Biological evidence can be contaminated by an officer's own body fluids. Avoid direct or indirect contact with biological evidence. Anything you touch with ungloved hands can leave your skin cells behind, which can contaminate DNA evidence. Contamination may also extend to the instruments used for collecting evidence.

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