“…there is a compelling argument that Pence’s use of the speech and debate clause is inconsistent with the clause’s purpose, which is to insulate members of Congress from pressure from the executive. It might also be argued (as retired judge Michael Luttig has) that Pence’s role on Jan. 6 was purely ceremonial, not legislative, and thus the speech and debate clause does not apply. After all, Pence himself argued that day that he had no legislative authority to nullify the electoral votes”
“Other scholars are even less tolerant of Pence’s argument. Constitutional experts Laurence H. Tribe and Dennis Aftergut argue that because Pence’s own prosecution is not at issue, he has little basis for resisting the subpoena. “Unfortunately for Pence’s claim, the Supreme Court ruled in 1972 that the clause does not ‘immunize a Senator or aide from testifying at trials or grand jury proceedings involving third-party crimes where the questions do not require testimony about or impugn a legislative act,’”
