A federal judge ruled Monday that former US President Donald Trump "more likely than not" engaged in criminal conduct with his efforts to overturn the results of the 2020 presidential election.

Judge David Carter leveled the accusation in a ruling dealing with subpoenas issued by the congressional committee investigating the January 6, 2021 attack on the Capitol by Trump supporters.

The ruling comes amid US media reports that Trump's son-in-law and senior advisor Jared Kushner is expected to appear voluntarily for a virtual deposition before the committee this week. 

"Based on the evidence, the court finds it more likely than not that President Trump corruptly attempted to obstruct the Joint Session of Congress," Carter said in a  44-page ruling.

Baseless election fraud allegations

The committee had sought documents from John Eastman, a conservative lawyer who provided legal advice to Trump in the wake of his November 2020 election loss to Democrat Joe Biden.

Carter, who serves on a US District Court in California, rejected Eastman's attempt to block handing over emails to the committee from his account at Chapman University, the California school where he was a law professor.

Eastman notably authored memos providing dubious legal arguments for how then-Vice President Mike Pence could swing the election to Trump when Congress met on January 6 to certify the results of the vote.

In his ruling, Carter noted that Trump had repeatedly urged Pence to throw out Electoral College votes from contested states and had done so in a fiery speech to his supporters shortly before the storming of Congress.

"Because President Trump likely knew that the plan to disrupt the electoral count was wrongful, his mindset exceeds the threshold for acting 'corruptly'," the judge said.

He added that Trump likely knew his allegations of election fraud were baseless, and therefore the plot was unlawful.

More than 775 people arrested

The judge's ruling may increase pressure on Attorney General Merrick Garland to bring charges against the 75-year-old Trump over the Capitol riot, which left at least five people dead and 140 police officers injured.

Garland has declined to reveal whether Trump is the target of any Justice Department investigation but has said the probe will continue "until we hold everyone accountable who committed criminal acts with respect to January 6."

More than 775 people have been arrested in connection with the Capitol attack. Some 280 have been charged with obstructing an official proceeding.

Trump was impeached for a historic second time by the House after the riot -- he was charged with inciting an insurrection -- but was acquitted by the Senate.

The judge ordered Eastman to disclose 101 documents to the House select committee investigating the January 6 attack while keeping 10 documents privileged.

The bipartisan panel, which is nearing the end of its investigation ahead of public hearings expected in May, launched criminal proceedings on Monday evening against Trump's trade director Peter Navarro and deputy chief of staff Dan Scavino.

It voted unanimously to ask the full Democratic-controlled House to cite the pair for criminal contempt of Congress after they refused to testify to the probe, in defiance of subpoenas.

The panel has previously recommended prosecution for senior Trump aides Mark Meadows and Steve Bannon, as well as ex-Justice Department official Jeffrey Clark.