Yesterday, the Senate Judiciary Committee looked into the idea of a commission to investigate possible criminal conduct by the Bush Administration. It was a curious affair, with Republicans joining together to criticize the commission concept on the grounds that it might get in the way of efforts to prosecute the Bush team. Daphne Eviatar of the Washington Independent summarized it this way:

“If there’s reason to believe that these Justice Department officials have given approval for things that they know not to be lawful and sound, go after them,” [Ranking Member Arlen Specter] said, referring to recent memos released from the Office of Legal Counsel that authorized extreme and arguably illegal executive powers. “Some of the opinions that are now disclosed are more than startling — they’re shocking.” The revelations, said Specter, who’s a former federal prosecutor, are “starting to tread on what may disclose criminal conduct,” he said. The witnesses called to support the Republican position seemed to agree.

David Rivkin, a former Justice Department official in the Reagan and first Bush administrations, called a truth commission “a profoundly bad idea, a dangerous idea, both for policy and for me as a lawyer for legal and constitutional reasons.” Such a commission “is to establish a body to engage in what, in essence, is a criminal investigation of former Bush administration officials,” he said. Matters such as the interrogation and treatment of terror suspects and domestic warrantless wiretapping, however, are “are heavily regulated by comprehensive criminal statutes.” Any such investigation, then, “ensures that the commission’s activities would inevitably invade areas traditionally the responsibility of the Department of Justice.” Rivkin went on to strengthen the case for a criminal prosecutions by arguing that if a commission were to unearth evidence of criminal activity and not prosecute it, it would leave former Bush administration officials open to prosecution abroad.

Of course, the Federalist Society and its network have adopted it as an article of faith that inquiries into abuses of presidential power by Republicans are a bad idea–which makes sense given how often these inquiries tend to come to a focus on Federalist Society members. But Rivkin is plainly correct that a commission and a team of federal prosecutors are likely to cross paths and get in the way of one another in sorting through the Bush mess.

The comments seemed to have clear impact on Senator Patrick Leahy, though perhaps not the way the Republicans imagined. After the hearing was over, he drew back on his vision of the role of amnesty in the process, suggesting in an interview with MSNBC’s Rachel Maddow that immunity would only rarely be granted and then in consultation with prosecutors at the Justice Department.

The hearing therefore seems to have been quite constructive: it has bridged differences between the House proposal backed by Speaker Pelosi, which is hostile to amnesty. The Leahy proposal hasn’t yet been reduced to writing, but it sounds more like the Conyers version every day.