Eve Fairbanks has hit on something interesting from a string of congressional scandals. Now, I think Larry Craig did get a bum rap - and his arrest was definitely mishandled and arguably unconstitutional.
But the worst are not people like Larry Craig, or Duke Cunningham, or John Doolittle, or Ted Stevens, or William Jefferson. It's folks who skate on things far worse than getting extra income on the side, to wit, Patrick Leahy and Robert Torricelli - politicians who leak secrets and continue to serve. Leahy still serves in the Senate twenty years after he was responsbile for the worst breach in security of the Senate Intelligence Committee (at the time, he still ranks as second-worst). Torricelli blew a source - and led to a purge of CIA assets - largely at the behest of his girlfriend at the time. He later went on to the U.S. Senate, where he served until some financial sleaze put him in a bad spot for re-election, and the Democrats had to pull a switcheroo.
But the double standard persists. Somehow, those who blow secrets and endanger national security are given a pass, particularly if they are Democrats, while a Republican who gets pinched in a very low-grade sting, and arguably should NOT have been arrested under the Constitution is now to be run out of town on a rail.