And they have.

The most common species is partisans' tendency to attack a nominee whose ideology they dislike for actions that the same partisans would applaud, or at least defend or dismiss as irrelevant, were the nominee's ideology more to the partisans' liking.

There are dozens, if not thousands, of examples. I will confine myself here to one especially pure paradigm, with compliments to a post by conservative expert Ed Whelan on National Review Online. Whelan's post compares the treatment of Judge Sonia Sotomayor with that of a lower-court nominee about whom I wrote a column in 2007.

(Disclosure: I, too, have recently been accused -- by far-left bloggers and others -- of applying a double standard by mildly criticizing then-sophomore Sonia Sotomayor's hyperbolic attack in 1976 on Princeton University for "institutional discrimination" while giving a pass in 2005 and 2006 to then-Judge Samuel Alito for legal memos he had written 20 years before. The criticism is bogus, as explained here.

The criticism also ignores the fact that in a 2006 television appearance, I mildly criticized Alito's testimony that he did not recall his brief association with the conservative Concerned Alumni for Princeton.)

Read Whelan's post after the jump: