here is a snip from Sen. Feingold's testimony today before the judiciary committee. I recommend the whole thing, but this part seemed pertinent to the thread:
http://www.commondreams.org/views06/0331-31.htm
We can fight terrorism without breaking the law. The rule of law is central to who we are as a people, and the President must return to the law. He must acknowledge and be held accountable for his illegal actions and for misleading the American people, both before and after the program was revealed. If we in the Congress don’t stand up for ourselves and for the American people, we become complicit in his law breaking. A resolution of censure is the appropriate response – even a modest approach.
Mr. Chairman, the presence of John Dean here today should remind us that we must respond to this constitutional crisis based on principle, not partisanship. How we respond to the President’s actions will become part of our history.