You (as are many others here) are confusing the Privilege from Arrest clause with the Speech and Debate clause. The first clause includes the felony exception; the second clause doesn't. Search and seizure of legislative materials is absolutely forbidden by the Speech and Debate clause. That doesn't mean Jefferson can't be arrested and prosecuted for bribery though.
In my posts on this thread, I have never resorted to the eponyms of "This Clause" or "That Clause". I have referred to the exact wording of "Article 1, Section 6".
The search and seizure of the evidence necessary to build a bribery case is NOT analogous to the search and seizure of legislative materials.
A bribery case is proved regardless of how the accused actually debated or voted or behaved himself in Congress by proving that illegal promises were made regardless of whether or not the illegal promises were actually kept.
The legislative material is irrelevant to the bribery case and there is no need to search or seize it for evidence.
The bribery evidence is relevant to the case, cannot be considered part of the legislative process by any stretch of the imagination and can be searched and seized and is a totally separate animal from "legislative material".
I seriously doubt that the FBI was searching for "legislative material" inside of the Congressman's freezer.
But, don't take my word for it. Take it from what Chief Justice Warren E. Burger wrote in UNITED STATES v. BREWSTER, 408 U.S. 501 (1972) :
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UNITED STATES v. BREWSTER, 408 U.S. 501 (1972)
The question is whether it is necessary to inquire into how appellee spoke, how he debated, how he voted, or anything he did in the chamber or in committee in order to make out a violation of this statute. The illegal conduct is taking or agreeing to take money for a promise to act in a certain way. There is no need for the Government to show that appellee fulfilled the alleged illegal bargain; acceptance of the bribe is the violation of the statute, not performance of the illegal promise.
Taking a bribe is, obviously, no part of the legislative process or function; it is not a legislative act. It is not, by any conceivable interpretation, an act performed as a part of or even incidental to the role of a legislator. It is not an "act resulting from the nature, and in the execution, of the office." Nor is it a "thing said or done by him, as a representative, in the exercise of the functions of that office," 4 Mass., at 27. Nor is inquiry into a legislative act or the motivation for a legislative act necessary to a prosecution under this statute or this indictment. When a bribe is taken, it does not matter whether the promise for which the bribe was given was for the performance of a legislative act as here or, as in Johnson, for use of a Congressman's influence with the Executive Branch. And an inquiry into the purpose of a bribe "does not draw in question the legislative acts of the defendant member of Congress or his motives for performing them."
Nor does it matter if the Member defaults on his illegal bargain. To make a prima facie case under this indictment, the Government need not show any act of appellee subsequent to the corrupt promise for payment, for it is taking the bribe, not performance of the illicit compact, that is a criminal act. If, for example, there were undisputed evidence that a Member took a bribe in exchange [408 U.S. 501, 527] for an agreement to vote for a given bill and if there were also undisputed evidence that he, in fact, voted against the bill, can it be thought that this alters the nature of the bribery or removes it from the area of wrongdoing the Congress sought to make a crime?
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