DNA not kept in half of states
Supporters of retaining DNA evidence point to a growing list of wrongly convicted prisoners who have been freed. But some prosecutors and lawmakers cite concerns ranging from cost to expanding DNA collections from individuals who have never been convicted of crimes.
Evidence preservation has been the key to freeing more than 200 wrongfully convicted prisoners, says the Innocence Project, a group that works to free the innocent based on DNA testing.
Preserving DNA also has helped secure convictions. "We're becoming more successful in identifying perpetrators in cold cases than we were when we didn't have this technology," says Scott Storey, district attorney in Jefferson County, Colo.
There is disagreement over how long and under what conditions to keep DNA. Storage space and extra costs are key issues. "I don't know if there is enough room to keep all of this evidence," Storey says. "I believe in the innocence movement, but you've got to have some common sense injected."
What states are doing: