With the possibility of a Senate vote of no confidence in AG Gonzales looming (and richly deserved), Bush Administration apologists have invoked the obvious but misleading point that a Senate vote of no confidence has no legal effect. This is a variation of the argument that was used during the Clinton impeachment effort. At the time, Democrats who agreed that Clinton had behaved inexcusably but thought that his conduct nonetheless did not warrant impeachment and/or removal from office, wished to see him censured instead. Republicans, wanting to prevent Democrats from having the "out" of a censure vote, insisted that because the Constitution describes the impeachment/removal procedure but does not mention censure, the latter option is unavailable. And likewise today, some Republicans who want to maneuver Iraq war critics into appearing not to support the troops insist that the only mechanism Congress has for stopping the war is a complete denial of funding.
The all-or-nothing argument is dubious in each context, although I'll restrict my analysis today to the Gonzales case. It's true that the only mechanism for removing a principal officer in the executive branch described in the constitutional text is impeachment. Yet that hardly proves that the Senate (or the House) can play no role in removal otherwise. If the textual argument were dispositive, then the President himself would not be permitted to remove a principal officer, except via impeachment. And yet Bush/Gonzales supporters plainly think that the AG serves at the President's pleasure. So the Constitution's reticence on this matter counts for precious little.
Nonetheless, there are sound structural reasons for believing---as the Supreme Court doctrine has more or less held---that while Congress can restrict the President's ability to remove some executive branch officials (as illustrated by the Independent Counsel case, Morrison v. Olson), Congress itself cannot retain the power to dismiss an executive branch official. A different rule would threaten the independence of the executive from Congress. But precisely because the President alone retains the ability to dismiss an executive branch official, absent the drastic step of impeachment, lesser steps by Congress are an entirely appropriate means of exerting political pressure. Withholding funding from agencies headed by sub-par performers is one method. Holding hearings at which executive officials publicly humiliate themselves is another. And a vote of no confidence is a third. If Congress can declare a "National Flag Week" or "Teacher Appreciation Week," as it has done, surely Congress can declare that "Alberto Gonzales is a lousy Attorney General," which is all that it would be doing in a vote of no confidence. Some might say it's the least Congress could do.