Oregon Public Broadcasting

Washington, Oregon and Idaho are among 25 states that don't require DNA evidence to be saved indefinitely.

That's according to The Innocence Project -- a group that works to exonerate the wrongly convicted. The group wants Northwest states to adopt model legislation. Olympia correspondent Austin Jenkins reports.

Say a person is convicted of murder. What happens to the evidence from that crime -- the blood stains, carpet samples, fingernail clippings?

In the Northwest, state law does not require that DNA evidence be saved for time immemorial.

Instead it's up to the state crime labs and individual police departments to decide what to save and for how long.

Rebecca Brown is with The Innocence Project in New York. She says too often evidence that could exonerate someone has been lost or destroyed.

Rebecca Brown: "You know we've had a lot of cases where we've been told the evidence just can't be found and then later it turns up where it wasn't supposed to be."

An official with the Washington State DNA lab says a blanket rule on preservation of evidence would be a good idea.

In Idaho, the state crime lab has a policy to save small DNA samples from crimes even though the law doesn't require it.