Here are a few places to look for further discussion of possible constitutional issues raised by the search of Rep. William Jefferson’s (D-LA) Capitol Hill office. First there are these posts by Bob Bauer (one, two and three). Here’s Marty Lederman laying out some of the key potential issues. And here’s Jack Balkin, who is not impressed with the arguments of Hastert and Pelosi.
In general, I stick by my earlier stated belief that there no separation of powers issues raised by the FBI executing a search warrant on a congressman’s office in the conduct of a bribery investigation. Especially, as in this case, when the target was refusing to turn over subpoenaed documents. However, Bauer does point to a development, which has gone largely unremarked, that I think does raise tangible separation of powers issues: the Justice Department’s decision to start conducting ‘interviews‘ with members of Congress to ferret out who was involved in the leaks of the NSA wire-tapping program.
I’ll leave the textual analysis to the law profs. But this kind of scrutiny of Congress is very much the sort of thing the constitution means to prohibit. Go back and read your English history and colonial history, the stuff the constitution writers had as their point of reference.