on the GOP's Pledge in Newsweek
Not so harmless, however, is the promise to require every bill to be certified as constitutional before it is voted on. We have a mechanism for assessing the constitutionality of legislation, which is the independent judiciary. An extraconstitutional attempt to limit the powers of Congress is dangerous even as a mere suggestion, and it constitutes an encroachment on the judiciary. Ramesh Ponnuru
correctly calls this line of thinking insane.
There’s nothing — nothing in the Constitution, nothing in Marbury v. Madison, nothing even in Cooper v. Aaron — that suggests that congressmen cannot consider the constitutionality of laws while voting on them. That they can do so, which one would have hoped would be a banal idea, does not even challenge judicial supremacy: The courts can still be the final arbiter of constitutionality. The Pledge provision in question is “extraconstitutional” only in the trivial sense that the Constitution neither requires nor forbids it.
Lithwick's equally dumb version of this train of thought here