FBI-search of congressional office constitutional

Another agency, another scandal? Not quite so. Still, the reaction to the FBI raid of the office of Representative William J. Jefferson (D-Louisiana) are interesting. In particular, GOP lawmakers expressed their outrage: Newt Gingrich, Dennis Hastert, John Boehner were among the group of republicans that expressed their concerns about this precedent (see NYT article).

It seems that they fear that future raids of other republicans may be possible now. Could this action be a warning of the president to possible dissidents in his party? An attempt to keep the party in one piece?

For some insightful legal discussion see Orin Kerr's comments. According to this, there doesn't seem to be any concern that such a search with a warrant is constitutional. Senators and representatives are protected by the Speech and Debate clause, Art. I, 6, cl. 1 to some extend though. I was, however, surprised that a concept of general immunity doesn't exist in the US. It seems that other countries have a much better protection for their members of the legislative branch.

Members of the German parliament, for example, enjoy immunity from prosecution. A raid of a MP's office would have been impossible without prior approval of the parliament.

Before the judiciary can take any action, the Parliament has to abrogate the immunity of each individual MP in question. Prosecution is usually possible if the MP has committed a serious crime like corruption or tax evasion. (source: global integrity)