On September 28, the Senate Judiciary Committee approved on a party line vote the nomination of Brian Benczkowski to be the head of the Justice Department’s criminal division. The vote put President Donald Trump one step closer to installing a potential mole at the department, with the ability to inform him of any wiretaps or significant developments in special counsel Robert Mueller’s grand jury investigation into the possible ties between Russia and the Trump campaign.

During the committee hearing, Democrats cited a number of reasons to oppose Benczkowski, who was a top aide to Attorney General Jeff Sessions when the former senator ran the Judiciary Committee. Senator Dianne Feinstein noted that Benczkowski, a partner at the firm Kirkland & Ellis, has no prosecutorial experience and almost no experience in a courtroom. Senator Dick Durbin and others argued that he showed “really poor judgment” when he chose to represent Alfa Bank, which has been implicated in the Russia scandal, between his stint on Trump’s transition team and his June nomination to be assistant attorney general. (Alfa Bank came under suspicion after it was discovered that one of its servers had communicated with a server tied to the Trump Organization.)

Senator Sheldon Whitehouse raised a more specific concern: that Benczkowski might serve as “a back channel source of information” from Mueller’s special counsel investigation to Sessions, who has recused himself from the case. Whitehouse and others fear that having Benczkowski as the head of the criminal division could effectively breach the recusal. But there may be a still bigger risk: Benczkowski could share information about wiretaps and proceedings from the grand jury directly with the president.

The cause for concern comes from an old Department of Justice interpretation of the PATRIOT Act. Along with expanding surveillance authorities, the PATRIOT Act permitted any government lawyer to share national security-related grand jury or wiretap information with any government official as long as it would help them perform their job better. The measure was passed in response to the September 11 attacks, with an eye to sharing counterterrorism information more broadly. But the authorization of such sharing explicitly extended to “clandestine intelligence activities by an intelligence service or network of a foreign power or by an agent of foreign power”—precisely the kind of nation-state spying at the heart of the Russian investigation.

A July 22, 2002, memo from the Justice Department’s Office of Legal Counsel, written by Jay Bybee, the author of the infamous torture memos, held that, under the statute, the president could get grand jury information without the usual notice to the district court. It also found that the president could delegate such sharing without requiring a written order that would memorialize the delegation.