The question isn’t “who watches the watchmen” in the Beltway today. It’s “who’s watching the watchers who watch the watchmen.” The head of the Senate Select Committee on Intelligence publicly accused the CIA of snooping a secure computer network set up as part of an investigation of the agency’s activities during the war on terror, following up on earlier hints of a war brewing between Langley and Capitol Hill:

The head of the Senate Intelligence Committee says the CIA improperly searched a stand-alone computer network established for Congress as part of its investigation into allegations of CIA abuse in a Bush-era detention and interrogation program. …

At issue is whether the CIA violated an agreement made with the committee about monitoring the panel’s use of CIA computers. The CIA provided the computers to congressional staffers in a secure room at its headquarters so that the committee could review millions of pages of top secret documents.

The Washington Post has more, including Feinstein’s blunt accusation that CIA attempted to intimidate the Senate into retreating on its oversight of the agency:

The head of the Senate Intelligence Committee on Tuesday publicly accused the CIA of secretly removing documents from computers used by her panel to investigate the agency’s controversial interrogation program and said that an internal agency investigation of the action has been referred to the Justice Department for possible criminal prosecution.

Sen. Dianne Feinstein (D-Calif.) said the activities of agency officials “may have undermined the constitutional framework” of congressional oversight.

The situation amounted to an attempted intimidation of congressional investigators, she said, adding: “I am not taking it lightly.”

Besides possible constitutional violations, Feinstein said the CIA may also have violated the Fourth Amendment, various federal laws and a presidential executive order that bars the agency from conducting domestic searches and surveillance. She said she has asked for an apology and recognition that the CIA search of the committee’s computers was inappropriate, but, “I have received neither.”

This, Jeff Zeleny notes, escalates a war that has been breaking out into the open over the last couple of weeks:

Needless to say, this comes at a bad time for the Obama administration. The original investigation had little to do with the Obama era; it was a probe into whether the CIA misled the Bush administration on interrogation and black-site operations in the early days of the war on terror. However, the agency has been under Obama administration control for over five years now, and its leaders are all Obama appointees. Even if the CIA was testing for leaks, it would have to work with Senate leadership to do so — and clearly that wasn’t the case if Feinstein’s going public this morning. And besides that, this would be the FBI’s jurisdiction, not the CIA’s, which is tasked with gathering foreign intelligence.

DNI James Clapper is already an unpopular figure for his misleading testimony to the Senate. John Brennan will sit in the hot seat this morning, with this storm in full rage. The upper chamber may be safely Democrat, but it’s likely to start asserting its constitutional powers — belatedly — over this intrusion on its authority, which would be stunning if it turns out to be true.

Update: Hmmmm.