A coalition of progressive groups on Thursday asked the Department of Justice (DOJ) to explain its internal policies on whether presidents can be charged with a crime.

Twelve defense and monitoring organizations sent a letter to Attorney General Merrick Garland is asking him to clarify the DOJ’s position as the House committee investigating the Jan. 6 attack builds its case that Trump broke the law to undermine the 2020 election results.

The groups said they were concerned that the department’s longstanding legal positions could prevent federal law enforcement from seriously considering the possibility of charging Trump with a crime despite mounting evidence that could justify charging him. prosecute under the same criminal laws the DOJ used against hundreds of Jan 6 rioters.

“If the Department of Justice finds that Presidents of the United States are exempt from 18 USC § 1512(c)(2) or any other criminal law based on a ‘Clear Statement Rule,’ it must tell the public and to Congress, to give Congress an opportunity to close this indefensible loophole,” the letter read, citing criminal law for obstruction of official process.

“If our fears are unfounded and the Department of Justice believes that former presidents are subject to the same criminal laws as all other citizens, it is entirely appropriate to reassure the public of that fact.”

Groups that signed the letter included: Project on Government Oversight, Citizens for Responsibility and Ethics in Washington, the Constitutional Accountability Center, Public Citizen and the Revolving Door Project.

A Justice Department spokesperson did not immediately respond when asked to comment on the letter.

Despite some signs that the DOJ’s Jan. 6 investigation has moved closer to Trump, it’s unclear whether the department’s leadership is seriously considering taking the unprecedented step of charging a former president with a crime.

The groups behind Thursday’s letter said they were concerned that binding legal memos from the DOJ’s Office of Legal Counsel (OLC) dating back decades could be seen as obstacles for investigators.

They asked Garland to explain specifically how a guideline known as the “Clear Reporting Rule” might apply. The rule, set forth in several OLC memos since the 1990s, states that the department must interpret criminal laws as “not applying to the president if such application would involve a potential conflict with the president’s constitutional prerogatives. “.

The OLC, which issues binding legal opinions to the entire executive branch, often protects its notes from the public. Advocates of open government say the opaque bureau is allowed to essentially create secret laws with little scrutiny.

In 2019, then-special counsel Robert Mueller said his office understood it was bound by OLC views that a sitting president could not be charged with a crime.

The president and attorney general have the power to rescind OLC advisories, but it’s still unclear which of the office’s memos remain in effect today, or whether department leadership is considering any of them. them as an obstacle to Trump’s investigation or prosecution.

“To the extent that non-public Department of Justice memoranda related to this topic exist, we urge you to make these memoranda available to Congress and the public,” the coalition of progressive groups wrote Thursday.