The US House panel investigating the January 2021 attack on the US Capitol will present evidence this week that former president Donald Trump was involved in a failed bid to submit slates of fake electors to overturn the 2020 election, a key lawmaker says.

“We will show evidence of the president’s involvement in this scheme,” Democratic congressman Adam Schiff, a member of the House of Representatives select committee, said on CNN’s State of the Union on Sunday.

“We will also again show evidence about what his own lawyers came to think about this scheme, and we’ll show courageous state officials who stood up and said they wouldn’t go along with this plan to either call legislatures back into session or decertify the results for Joe Biden,” he said.

Mr Schiff’s comments came as the Democrat-led committee prepares to hold its fourth public hearing on Tuesday on their investigation into the January 6, 2021, attack and Trump’s role in trying to block Congress from certifying Biden’s election victory.

Evidence against Mr Trump could potentially be crucial in an ongoing criminal investigation by the Department of Justice (DOJ) into the alleged fake elector plot.

In an interview with CNN earlier this year, Deputy Attorney-General Lisa Monaco confirmed the department had received referrals about slates of alternative fake electors that were sent to the National Archives, and said prosecutors were reviewing them.

In March, the non-profit watchdog group American Oversight published copies of the phoney electoral slates, which had been assembled by groups of Trump supporters in Arizona, Georgia, Michigan, New Mexico, Nevada, Pennsylvania, and Wisconsin.

Since then, the DOJ has convened a grand jury to subpoena witnesses and documents as part of the probe, multiple media outlets have reported.

Jamie Raskin, another Democratic member of the panel, told NBC’s Meet the Press that new information and tips kept coming in.

“There are still people who are turning over information to the committee,” he said. “We know things this weekend that we didn’t know last weekend.”

Mr Trump, meanwhile, has continued to peddle false claims that the 2020 election was stolen. On Friday, he lashed out at former vice-president Mike Pence, saying he “did not have the courage to act” and reject the 2020 election results.

– AAP