False positives

Kevin Drum writes:

Set aside the states' right argument for now.  I'm more interested in the question of whether constitutional protections for DNA testing would, in fact, result in lots of frivolous demands and endless appeals.

If there were, literally, no restrictions at all, maybe that's what would happen.  Maybe every con with time on his hands would demand test after test just for the hell of it.  Maybe.  But if the court required even a minimal showing of cause, wouldn't frivolous requests dry up?  What's the point, after all?  If you're guilty, then you know perfectly well that DNA isn't going to get you off the hook.  So why bother?

That's why I've never found this argument very persuasive.  Prisoners who know they're guilty have little incentive to demand DNA tests.  Conversely, though, prosecutors have loads of incentive to deny DNA tests, even -- or maybe especially -- in cases where it might well prove wrongful conviction. 

Actually, I'm told that a shocking number of prisoners request DNA tests that confirm their guilt; they have nothing to lose, and apparently want to gamble on the slim possibility of a miracle exoneration.  But this seems irrelevant to me.  If they get a DNA test and it proves them guilty, we've lost little time or money.  If they get a DNA test and it exonerates them, we've set an innocent man free.  DNA tests would have to cost $1 million apiece for me to consider that a bad bargain.

It is, of course, a bad bargain for a justice system that suddenly reveals how many innocent men prosecutors have sent to death row, and if I were a prosecutor I've no doubt I could find any number of excellent reasons that we should not double-check my work.  But making prosecutors feel better about themselves is not a legitimate goal of criminal policy.