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Collecting DNA Evidence at Property Crime Scenes

Testifying

Testifying

Photo of an empty courtroom with a testifying stand
National Institute of Justice (NIJ) (see reuse policy).

The well-documented research of forensic DNA analysis methods, along with the National Quality Assurance DNA Standards, limit the challenges against the underlying science used in forensic DNA laboratories. However, the investigator may encounter challenges originating from evidence identification, note taking, collection procedures and proper chain of custody.

All law enforcement notes, reports, photographs, laboratory analysis reports and chain-of-custody records are kept in the case file, which is made available to the prosecution and is subject to discovery by defense counsel. The chain of custody operates like a chain; if one link is broken, the chain breaks and the evidence may be ruled as inadmissible.

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