I'm no lawyer, but if I'm reading this correctlty, either Sgt. at Arms can arrest Bush's people if they are found in contempt.
"It is conceded that the Senate was engaged in an inquiry which it had the constitutional power to make; that the committee1 had authority to require the production of papers as a necessary incident of the power of legislation; and that the Senate had the power to coerce their production by means of arrest. McGrain v. Daugherty, 273 U.S. 135 , 47 S.Ct. 319, 50 A.L.R. 1. No. question is raised as to the propriety of the scope of the subpoena duces tecum, or as to the regularity of any of the proceedings which preceded the arrest. The claim of privilege hereinafter referred to is no longer an issue."
