Some enterprising pundits have pointed out that House Republicans who want to suspend the salaries of members of Congress until they pass a budget would be violating the 27th Amendment. The Amendment states:
No law, varying the compensation for the services of the Senators and Representatives, shall take effect, until an election of Representatives shall have intervened.
While seemingly aimed at preventing Congressmen from raising their own salaries, the text of the Amendment also seems to prohibit reductions too -- hence the prohibition on "varying" the compensation, not "increasing" the compensation. But the ban only applies during the current Congress. So, if the House wanted to restrict salaries until a budget is passed, it could only include a provision that takes effect in 2015.
There's a counterargument that since the money is only 'withheld' if a budget isn't passed (i.e., members get all the pay they're past due once a budget is finished), that it doesn't really amount to a reduction in pay. But I think even withholding is a variation in their compensation. If any of us in the private sector had our salaries withheld, does anyone doubt that we would be yelling and screaming that we had an effective pay cut?
I've always thought the story of the amendment is far more interesting than its actual substance. The amendment was originally part of the Bill of Rights. When Congress sent the Bill of Rights to the states, it actually had other amendments that were not ratified. Eventually, the necessary three quarters of states approved this amendment after a college student at the University of Texas discovered that this one was still waiting. It raised the interesting question about how long a state's ratification of an amendment is good for -- do they ever have an expiration date? Apparently, no court ruled on this -- the decision was made, I believe, by the Archivist of the United States, who concluded that ratifications do not expire on their own.
Another interesting angle: Michael Paulsen of St. Thomas Law School has argued that calls for a constitutional convention similarly have no natural expiration date. He asserts that enough states, over the years, have called for a constitutional convention, and that one should be called forthwith!