In 2008, California became the first state in the nation to adopt a familial DNA policy. Under the policy, familial DNA is only to be used as a "last resort" when all other investigative angles have been exhausted. In some instances, detectives search the database several times for the same case. In the case of the Grim Sleeper killer, an initial search turned up nothing, but state officials ran another scan in 2010.

Source: Los Angeles Times April 26, 2018 21:53 UTC