Article 1, Section 6 says:
They shall in all cases, except treason, felony and breach of the peace, be privileged from arrest during their attendance at the session of their respective Houses, and in going to and returning from the same; and for any speech or debate in either House, they shall not be questioned in any other place.OK, bribery is technically a felony, so the DOJ is in the clear here, at least to my untrained eye. However, did they need to do things the way they did?
This provision was not put into the Constitution for kicks - or for Robert Byrd to get out of traffic tickets. The Founders had good reason to put what looks like blanket protection while engaged in the course of their duties. How hard would it be for a President to use the FBI or other government agencies to intimidate Congress into passing controversial legislation or to not look into things that ought to be looked into? Not very, and in this day and age of complicated "reform" laws, it could be easy to trip up a Congressman on a technical violation of the law... which would be overlooked in exchange for consideration on certain things.
I don't ever recall a need to search a Congressman's office. Ever. Congressman Jefferson has pushed us to a situation that is very difficult for all involved. We cannot tolerate elected officials selling favors. But the protections for Congressmen and Senators from potential intimidation need to be preserved as well. This is what has Hastert worried, and his concern for this should not be treated the way it has been elsewhere.