A “DNA sweep” or “DNA dragnet” refers to the practice of police officers asking large numbers of people to voluntarily give DNA samples in order to help solve a crime. It is a controversial practice that is infrequently used because it can easily impose on what the New York Times has called “constitutional protections against compelled self-incrimination and unreasonable search and seizure.”
The principle that participation is voluntary is fragile, since refusing is interpreted by at least some police officials as itself constituting probable cause for the search. When DNA collections occur at a workplace, particularly when workers’ employment is insecure, people can face particular pressure to comply.
Read the full, original story: Discriminatory “DNA Sweeps”