Democratic Rep. Lloyd Doggett said Tuesday that IRS Commissioner Charles Rettig and Treasury Secretary Steven Mnuchin should be jailed or fined for stonewalling congressional subpoenas for President Trump’s tax returns.

Doggett, D-Texas, a member of the House Ways and Means Committee, said Tuesday that congressional Democrats need to employ what's known as "inherent contempt" for Trump officials defying committee requests and subpoenas for Trump’s financial information.

CONFIDENTIAL DRAFT IRS TAX MEMO SAYS TAX RETURNS MUST BE HANDED TO CONGRESS UNLESS TRUMP ASSERTS EXECUTIVE PRIVILEGE: REPORT

“I believe that there is no legal advice that will stop the lawlessness and lies of this administration, and that is why Congress needs to act firmly now to use every tool it has available to get this information that Trump so fears that the public will see,” Doggett told MSNBC’s Rachel Maddow Tuesday night.

“To take action, I believe it’s going to require fines or confinement under our power of inherent contempt to get the information we need and to get all these other people that, under what seems to be gang rule, are told don’t say anything and don’t provide anything,” he continued. “Total silence, total obstruction.”

Doggett later clarified who should be targeted in that effort.

“The subpoena is directed to the IRS commissioner,” Doggett explained. “But Secretary Mnuchin has never let him answer the questions—he responds with all the answers.”

“I think that both of them could be subject to fines or confinement,” he said. “I think you know there are so many people out there from [former White House counsel Don] McGahn to [Attorney General Bill] Barr, to others that are refusing to disclose and respond to the Congress.”

He added: “It’s probably a matter of selecting one of them and moving forward to show how this power of inherent contempt could work.”

Inherent contempt is one of three contempt options available to Congress, along with criminal contempt (under which an individual is charged with a crime) and civil judgment (leading to a civil court process.)

If Congress were to use inherent contempt, it would mean the Sergeant at Arms would arrest an official and hold them until they provide testimony or otherwise comply. The tactic reportedly has not been used since the 1930s, and is viewed as an extreme measure.

Congressional Democrats, though, already have threatened to take such action against Barr, who defied a subpoena issued by the House Judiciary Committee for an unredacted version of Special Counsel Robert Mueller’s report and all underlying evidence and documents. The Democrat-led committee has already recommended some form of contempt citation against Barr, while Democrats have threatened to pursue the same against McGahn after he defied a subpoena to testify before the same committee.

MNUCHIN SAYS HE WON'T COMPLY WITH SUBPOENA FOR TRUMP'S TAX RETURNS

The calls for Rettig and Mnuchin to be jailed, though, come amid a growing battle between the Trump administration and Congress, specifically the House Ways and Means Committee, over the president’s financial documents.

Just days after Mnuchin said he would not comply with a subpoena for the tax returns, a confidential draft IRS memo obtained by The Washington Post called the disclosure “mandatory,” unless the president asserts his executive privilege.

The Post published the 10-page memo that does not mention Trump by name, but appears to add new pressure on the White House. Mnuchin, though, has been resisting House Democrats’ requests for Trump’s tax returns on the grounds that such a request “lacks a legitimate legislative purpose” and said his department will not “disclose the requested returns and return information.”

But the IRS document says the law “does not allow the Secretary to exercise discretion in disclosing the information provided the statutory conditions are met” and directly rejects the reason Mnuchin has cited for withholding the information.

“[T]he Secretary’s obligation to disclose return and return information would not be affected by the failure of a tax writing committee … to state a reason for the request,” it reads, adding that the “only basis” for refusing would be “the invocation of the doctrine of executive privilege.”

But the IRS pushed back on the report, stating that the memo does not represent an official position for the agency.

“The memo in question is a draft background paper that was never finalized. It is not the official position of the IRS. The document was prepared last fall,” an IRS spokesperson said in a statement to Fox News. “The IRS Commissioner and the Chief Counsel were unaware of the paper until this week’s media inquiry. The document was not sent to Treasury.”

It is unclear whether the president would have to assert executive privilege to protect his financial documents from being exposed.

At a House Financial Services hearing on Wednesday where the tax return issue was front and center, Mnuchin testified that he never talked to anyone at the White House, or the president, about handing over tax returns to Congress.

Addressing the IRS memo, Mnuchin said he did not believe it contradicts his conclusion that Congress needs a "legitimate legislative purpose," and said the memo addresses a "different issue." Mnuchin also said the administration is in the process of finding out who penned the memo.

The standoff between the congressional Democrats and the administration is likely to lead to a court battle, with Trump reportedly indicating he’s prepared to fight all the way to the Supreme Court.

Trump declined to reveal his tax returns during the 2016 presidential election, claiming he was under audit. Political candidates aren’t required to disclose their tax returns, though traditionally all candidates do.

Fox News’ Lukas Mikelionis, Kristin Brown, and The Associated Press contributed to this report.