The additional step, which takes only seconds, was mandated by a new law requiring people accused of violent crimes to submit DNA samples. And already has generated clues to 21 unsolved criminal cases, including one killing and at least three rapes, officials said.
Fairfax County police this month charged an Annandale man with indecent exposure based on a match in the new system. And Richmond police said a genetic fingerprint of a new suspect linked him to a beer can found at the scene of a fatal shooting.
Officials with the state office of the American Civil Liberties Union said they are monitoring the law but have found no solid legal argument to challenge it.