MEMBERS OF CONGRESS ARE COMPLAINING about the FBI raid on Rep. William Jefferson's office. The separation of powers argument seems to be pretty weak to me: The actual scope of Congressional immunity under the speech and debate clause is quite narrow (narrower, oddly, than the judically-created immunities enjoyed by judges and prosecutors) and certainly doesn't include immunity from search in a bribery case.
At any rate, members of Congress who are offended by an unannounced late-night raid on an office might profitably be asked what they think about late-night unannounced raids on private homes, which happen all the time as part of the Congressionally-mandated War on Drugs.
If anything, it ought to work the other way. I think if you searched 435 randomly selected American homes, and 435 Congressional offices, you just might find more evidence of crime in the latter. . . .
One can almost hear Speaker Hastert trying to defend himself: ”Look, I said something about executive branch overreaching just this morning. Ya know, I’ve signed off on some extraordinary police powers over the years, but there’s gotta be a limit to those powers. The Constitution is clear: The right of members of Congress to be secure in their offices and homes shall not be violated!”