Senate Minority Whip Dick Durbin, D-Ill., threw his support Sunday behind Senate Intelligence Committee Chairwoman Dianne Feinstein's claim that the CIA might have spied on Senate staff.

"Dianne Feinstein believes that's the case -- I'll stand behind her," Durbin said of the California Democrat, though he also called for an investigation to "get to the bottom" of the allegations.

Feinstein said on the floor last week that the CIA might have ran afoul of the Constitution by allegedly blocking a Senate investigation on the agency's interrogation tactics. She said the CIA hacked into computers used by Senate staffers during the committee's probe.

Feinstein, one of the intelligence community's biggest Senate boosters, said the alleged action interfered with the Senate's oversight duties.

"I have grave concerns that the CIA’s search may well have violated the separation of powers principles embodied in the United States Constitution," she said on the floor.

CIA Director John Brennan denied the agency hacked Senate staffers' computers.

"As far as the allegations of, you know, CIA hacking into, you know, Senate computers, nothing could be further from the truth. I mean we wouldn’t do that. I mean that’s just beyond the — you know, the scope of reason in terms of what we would do," he said last week at a Washington event hosted by the Council on Foreign Relations.