William Barr testified before a Senate Appropriations subcommittee on Wednesday and made headlines for promising to investigate former Obama officials who began the counter-intelligence probes into members of President Trump’s 2016 campaign.

There was a lesser noticed moment of his testimony, though, that should have perked up the ears of House Judiciary Committee chairman Jerry Nadler if he was listening.

During questioning from Republican Sen. Shelley Moore Capito, Barr acknowledged that there was precedent for releasing the entire unredacted Mueller report to Congress. This contradicts what he has said repeatedly over the course of two days of testimony, in which he has been adamant that there is no way around rules governing grand jury secrecy.

The exchange in question came roughly midway through the two-hour testimony. Capito was attempting to solicit a response from Barr explaining how crazy it would be for Congress to receive grand jury information. Here’s the key portion:

Capito: We hear a cry on Capitol Hill to release the entire report. I just want to reemphasize what you stated [..] that would be a very unprecedented and damaging to just put the whole thing out there and an unreasonable request. Am I stating that correctly. Barr: I don’t know if it would be unprecedented since I’m not really sure what happened in the Watergate situation. I know the report came out 50 years later, I think.

At this point, Capito attempted to steer the conversation back on course, Barr stuttered for a moment, and then returned to her line of argument. “It’s essentially unprecedented, I would say,” he concluded.

“Essentially unprecedented” is not “unprecedented.” And Barr, the incredibly smart Washington lawyer that he is, noted the perfect precedent: Special Prosecutor Leon Jaworski’s cooperation and sharing of confidential grand jury materials with the House Judiciary Committee during the Watergate inquiry.

In that case, which Barr brought up, a “Road Map” for impeachment from the Watergate grand jury itself was released publicly last October after 44 years of being sealed by the court. However, that Road Map—with all of the secret grand jury material that it included—was sent at the time of the Watergate investigation directly to Congress for consideration.

As Jaworski wrote in his memoir, the decision to send the report to the judiciary committee at the time was “without legal precedent, but it seemed to be legally proper—if we prepared the information properly.”

Indeed, after Watergate, sending grand jury materials to Congress for the purposes of an impeachment inquiry is no longer without precedent. This is, in fact, the precise precedent that should guide Barr.

Unfortunately, the attorney general has repeatedly said he won’t be following that precedent. Instead, he has claimed—again contrary to the precedent he himself cited—that there’s likely no way around the Federal Rule of Criminal Procedure 6(e) against revealing grand jury information.

In testimony before a House appropriations subcommittee on Tuesday, for example, Barr said that Nadler would have to “go to court” if he wanted access to the full prosecutorial report. On Wednesday before the Senate appropriations subcommittee, he hedged a bit and said he would try to work with the judiciary committees in both houses of Congress to see what he could give them. But he also emphasized multiple times that he would not be able to work around 6(e).

“The category that I think is the most inflexible under the law right now is the grand jury material,” Barr told the Senate subcommittee.

The attorney general added that he didn’t think that there was any request Nadler could make that would be covered by one of the multiple exceptions to 6(e). “If someone shows me and makes a persuasive argument that it’s covered, then I’m willing to listen to that, but I don’t see it,” he said.

The statute in question, however, states that exceptions be made for any “judicial proceeding.” A district court that ruled just last week on the issue of grand jury secrecy in another case stated that the Watergate precedents still held and that grand jury information could be released to Congress in connection with an impeachment inquiry, which would constitute a “judicial proceeding.”

In accidentally revealing his legal knowledge of the governing precedent, Barr showed how hollow his position of withholding the full report from Congress is. Should he force the issue and press the judiciary committee into taking the matter to court, the committee’s attorneys should cite Barr’s own words acknowledging the actual governing precedent against him.