Last summer, it transpires, the FBI had searched his home and found $90,000 in his freezer. The details are especially useful for tabloid exposure. If you keep $90,000 in greenbacks inside your freezer, it is reasonably guessed that you had some reason to keep them there instead of at your bank. It is possible to imagine a situation in which the freezer turned out to be the best place to put the stuff -- say, a fire threatened your apartment -- but the protagonist hasn't given this reason to his constituents, who are skeptical.
The issue was almost immediately raised that the FBI agents were exercising themselves outside their constitutional competence. This vague point has affected the thinking of those who are attracted to theoretical extrapolations on the Bill of Rights, taking its provisions to lengths that would surely have surprised the Founders. If the Constitution's rule separating church and state can be held to mean that a replica of the scene at Bethlehem cannot be constitutionally displayed on state property, then maybe Mr. Jefferson is indeed protected, giving credibility to the new Hastert-Pelosi exegesis of the Constitution.
But stare down hard at the language. The Constitution holds that lawmakers are "privileged from arrest during their attendance at the session of their respective Houses, and in going to and returning from the same."
That provision was intended to protect legislators from arrest for statements made in the course of their legislative duties. This has nothing to do with Mr. Jefferson's case. Which means that those who say that the FBI should not have had access to the congressman's home or office are extending that constitutional provision to the point of immunity from search.