The committee announced that Trump’s campaign manager, Bill Stepien, is among the witnesses scheduled to testify at a hearing on Monday that focuses on Trump’s effort to spread his lies about a stolen election. Stepien was subpoenaed for his public testimony.

As the hearings unfold, Representative Adam Schiff said he would like the department to “investigate any credible allegation of criminal activity on the part of Donald Trump”.

Schiff, a Democrat who also leads the House intelligence committee, said “there are certain actions, parts of these different lines of effort to overturn the election that I don’t see evidence the Justice Department is investigating”.

The committee launched its public hearings last week, with members laying out their case against Trump to show how the defeated president relentlessly pushed his false claims of a rigged election despite multiple advisers telling him otherwise and how he intensified an extraordinary scheme to overturn Joe Biden’s victory.

Additional evidence is to be released in hearings this week, Democrats say, that will demonstrate that Trump and some of his advisers engaged in a “massive effort” to spread misinformation, pressured the Justice Department to embrace his false claims, and urged then-vice president Mike Pence to reject state electors and block the vote certification on Jan. 6, 2021.

Stepien, a longtime Trump ally, is now a top campaign adviser to the Trump-endorsed House candidate in Wyoming’s Republican primary, Harriet Hageman, who is challenging Liz Cheney, the committee’s vice-chair and a vociferous critic of the former president.

A Trump spokesman, Taylor Budowich, suggested the committee’s decision to call Stepien was politically motivated.

Monday’s witness list also includes BJay Pak, the top federal prosecutor in Atlanta who left his position on January 4, 2021, a day after an audio recording was made public in which Trump called him a “never-Trumper”; Chris Stirewalt, the former political editor for Fox News; noted Washington elections lawyer Benjamin Ginsberg; and Al Schmidt, a former city commissioner in Philadelphia.

The panel will also focus on the millions of dollars Trump’s team brought in fundraising in the run-up to January 6, according to a committee aide.

Committee members said they would present clear evidence that “multiple” GOP lawmakers, including Republican House member Scott Perry had sought a pardon from Trump, which would protect him from prosecution.

Perry on Friday denied he ever did so.

Lawmakers indicated that perhaps their most important audience member during the hearings may be Attorney-General Merrick Garland, who must decide whether his department can and should prosecute Trump.

A prosecution would be unprecedented and may be complicated in a political election season in which Trump has openly flirted with the idea of running for president again.