In his report, Mr. Conyers cites a catalogue of good-government laws that flowed out of Richard Nixon’s impeachment: the Federal Campaign Finance Act, the Foreign Intelligence Surveillance Act, the Independent Counsel Act, the Ethics in Government Act, and the Presidential Records Act.

Whatever the original rationale for such laws, the rankest impulses in politics soon turned them into weapons to take down officials in a government one can’t overthrow by other means. You could fill the whole House chamber with men and women who since Watergate have been driven out and bankrupted by them. Criminalizing policy differences has become the modern version of bills of attainder…

Thus arrives the Geithner Exception. Getting to be Treasury secretary may be more than Mr. Geithner deserves. This is an opportunity, though, to admit that giving someone’s government a chance to function, assuming that’s any longer possible, is a greater public good than witch-burning.