The House select committee investigating the Capitol attack recommended on Wednesday the criminal prosecution of the former Trump justice department official Jeffrey Clark, over his refusal to comply with a subpoena in the inquiry into the 6 January insurrection.

The select committee approved the contempt of Congress report unanimously. The resolution now heads to the full House of Representatives, which could refer Clark for prosecution in a vote that could come as soon as next week.

Bennie Thompson, the chairman of the select committee, said at the vote to report Clark in contempt that the panel was seeking his criminal prosecution to demonstrate their resolve in enforcing subpoenas, and to warn other Trump aides about the penalties for non-compliance.

“The select committee has no desire to be placed in this situation but Mr Clark has left us no other choice. He chose this path. He knew what consequences he might face if he did so. This committee and this House must insist on accountability,” Thompson said.

But the select committee gave Clark one final opportunity to escape a referral to the justice department for prosecution by appearing at a new deposition on Saturday, after his attorney said in an 11th-hour letter that Clark now intended to claim the fifth amendment.

“The committee would certainly consider that we will not finalize his contempt process if Mr Clark genuinely cures his failure to comply with the subpoena this Saturday,” the vice-chair of the select committee, Liz Cheney, said at the vote.

The reprieve for Clark means that the select committee may ultimately take no action against him, even if he claims the fifth amendment – his right to protect himself against self-incrimination – for almost every question put before him at the deposition on Saturday.

“The fifth amendment is part of the constitution. Our committee is here to defend the constitution against a violent assault,” said the select committee member Jamie Raskin. “So we’re not going to begrudge anyone an honest invocation of the fifth amendment.”

“If he thinks that his communications with Trump or anyone else reveal criminal activity, and he has a reasonable fear that that can be used against him, then he’s got an opportunity to exercise the fifth amendment,” Raskin said.

That could mean House investigators learn nothing more about Clark’s role in Trump’s scheme. But if Clark testifies under immunity, he would then have to respond truthfully to all questions asked by the select committee.

Raskin told reporters after the vote that the contempt report would next go to the House rules committee, which would prepare it for a full House vote, which remains on the table should Clark not cooperate to a satisfactory degree at his new deposition.

The select committee’s recommendation could bring grave consequences for Clark: if the report is passed by the House, the justice department is required to take the matter before a federal grand jury, which last month indicted the former Trump adviser Steve Bannon over his subpoena defiance.

In his opening statement before the vote, Thompson noted that Clark’s attorney had sent a letter to the select committee late on Monday night stating that Clark had experienced a late change of mind and would claim fifth amendment protection.

But Thompson said even though the select committee would provide Clark an opportunity to assert that protection at a second deposition on Saturday, he viewed the move as “a last-ditch attempt to delay the select committee’s proceedings” and would proceed with the vote to recommend his prosecution.

The select committee would only move to halt the contempt of Congress proceeding if Clark demonstrated that he intended to fully cooperate with House investigators, Liz Cheney, the vice chair of the select committee said in her opening statement.

A successful contempt prosecution could result in up to a year in federal prison, $100,000 in fines, or both – although the misdemeanor offense may not ultimately lead to his cooperation, and pursuing the charge could still take years.

The select committee subpoenaed Clark last month as it sought to uncover the extent of his role in Donald Trump’s scheme to subvert the results of the 2020 election and stop the certification of Joe Biden’s election win on 6 January.

Thompson said at the time that the subpoena, which followed a Senate judiciary committee report detailing Clark’s efforts to abuse the justice department for Trump, also sought to identify who else in the Trump administration had been involved in the scheme.

But after Trump issued a directive to former aides to refuse to cooperate with the investigation, even though Clark agreed to appear before investigative counsel at a deposition, he declined to answer questions broadly citing attorney-client and executive privileges.

The select committee on Tuesday rejected those arguments, saying Clark had no basis to refuse his subpoena on grounds of privilege because Trump had never formally asserted the protections – but also because Clark tried to use executive privilege for non-privileged material.

“Mr Clark refused to answer questions regarding whether he used his personal phone or email for official business, when he met a specific member of Congress, and what statements he made to media,” the contempt report said, “none of which involve presidential communication.”

The contempt report added that even if the select committee had accepted his executive privilege claim, the law made clear that even senior White House officials advising sitting presidents don’t have the kind of immunity from congressional inquiries being claimed by Clark.

The select committee also objected to the argument by Clark’s counsel that he could not respond to the panel’s questions until the courts resolved whether Trump could use executive privilege to block the National Archives from turning over White House documents.

“This is not a valid objection to a subpoena, and the select committee is not aware of any legal authority that supports this position,” the report said. “The issues raised in the National Archives litigation are wholly separate and distinct from those raised by Mr Clark.”

Ahead of the select committee’s vote to recommend prosecution, Clark’s attorney, Harry MacDougal, disagreed and told Thompson in a letter that Clark could not testify until the National Archives case was decided.

“He is duty-bound not to provide testimony to your committee covering information protected by the former president’s assertion of executive privilege,” MacDougalsaid of Clark in the letter. “Mr Clark cannot answer deposition questions at this time.”

The Senate report found Clark had played a leading role in efforts to overturn the results of the 2020 election, leveraging his role at the justice department to do Trump’s bidding and pressure the then acting attorney general, Jeff Rosen, to avow debunked claims of fraud.

It detailed, for instance, a 2 January confrontation during which Clark demanded that Rosen send Georgia election officials a letter that falsely claimed the justice department had identified fraud – and threatened to push Trump to fire him if he refused.

The move to recommend the criminal prosecution of Clark for contempt marks the second such confrontation, after the select committee last month voted unanimously to hold Bannon in contempt of Congress for also ignoring his subpoena in its entirety.

Bannon also cited Trump’s directive, first reported by the Guardian, for former aides and advisers to defy subpoenas and refrain from turning over documents, in his refusal to cooperate with the select committee’s investigation.

Bannon was indicted on two counts of contempt of Congress by a federal grand jury earlier in November. He has pleaded not guilty and vowed to “go on the offense” against Biden and the select committee.