U.S. flag

An official website of the United States government, Department of Justice.

Principles of Forensic DNA for Officers of the Court

Method of Obtaining the Known Sample

Home  |  Glossary  |  Resources  |  Help  |  Contact Us  |  Course Map

In some jurisdictions, a DNA sample is routinely taken from an arrestee in a process similar to booking and fingerprinting. In all cases, however, the method of obtaining a DNA sample must comply with constitutional requirements.

The U.S. Supreme Court has permitted police to seize, without a warrant, physical evidence from a lawfully arrested person. In United States v. Edwards, police were allowed to seize an arrestee's clothing to look for paint chips that matched evidence at the crime scene. However, Edwards may be limited by two facts: There was clear probable cause linking the clothing to the crime scene, and a search of clothing for paint chips is not a physically intrusive one. 10

Because this issue remains unresolved at this time, police or prosecutors may elect to obtain a court order or warrant to permit the obtaining of a DNA sample.

composite image of fingerprints on the left side an equal symbol with a question mark in the center and an illustration of dna on the right
National Institute of Justice (NIJ) (see reuse policy).

Back Forward