There's no excuse for driving drunk. If you're gonna be imbibing, just call for a cab or crash with a friend. It's not worth the risk to yourself or the public.
That said, some DUIs definitely worse than others.
There are the Stephanie Pratt-style arrests, in which the person registers a BAC of exactly .08, and legitimately felt they were in good condition to drive.
Then you have Chris Klein early this morning, bombed out of his mind at ...