Wisconsin law requires that people convicted of felony offenses are required to submit a sample of their DNA.
DNA evidence is also collected from crime scenes, and even if the identity of the person who committed the crime is unknown, a warrant can be issued based solely on the genetics found in the DNA sample.
Those samples then become part of a national database, which police say is a valuable tool to help solve past and future cases.
"When and if a name ever comes up it gets attached to that no longer John Doe," says Sgt. Judy Anibas. "It puts the person's actual name on it and then that warrant is valid until we catch that person."
Since 2000, Sgt. Anibas estimates there have been four cases in Eau Claire solved by DNA evidence.