Jan. 6 hearing shows Barr saying Trump 'detached from reality' in pushing 'big lie'

Former Fox News political editor Chris Stirewalt, who was fired after defending the network's early projection that Trump had lost Arizona on election night, has written a blog post for The Dispatch, a right-leaning politics website, explaining why he agreed to testify before the Jan. 6 committee.

"I’m still not entirely sure what I will say or what may happen, and don’t want to close any doors or create any expectations. I had a pretty good perch for the 2020 election and was part of the best decision desk in the news business on election night," he said. "I’m still so proud of the work we did -- we beat the competition and stuck the landing. All I can do is tell the truth about my work and hope for the best."

Former Trump 2020 campaign manager Bill Stepien told the House select committee that his wife went into labor this morning, according to two sources briefed on the matter, explaining the family emergency that caused him to cancel his live appearance before the committee.

Stepien previously sat for a taped deposition before the committee, and vice-chair Liz Cheney told reporters to expect video excerpts of that deposition played Monday.

ABC News' Chief Washington Correspondent Jonathan Karl and Benjamin Siegel

Rep. Liz Cheney, R-Wyo., vice chair of the committee, told reporters to prepare for a substantial hearing despite Trump's former campaign manager Bill Stepien having to drop out from testifying live at the last minute due to a family emergency.

"We're going to have a very important and effective set of hearings. As you know, Mr. Stepien has appeared previously, and so we'll be able to provide the American people with a lot of interesting new and important information that Mr. Stephens provided to us previously," Cheney said.

She also confirmed the committee will show video of Stepien's interview.

In previewing Monday's hearing, which will be guided in part by Rep. Zoe Lofgren, D-Calif., House select committee aides said members would focus on how Trump and his campaign pushed the 'big lie' to millions of supporters after the election, despite knowing he lost.

The questioning of live witnesses, along with clips of interviews the committee videotaped with other key witnesses, will show how Trump was told he had lost the election and lacked evidence of widespread voter fraud but continued to claim the election was stolen from him, aides told reporters on Sunday night.

The committee hearing will show "how litigation to challenge elections usually works," and argue that Trump had an "obligation" to "abide by the rule of law" when his dozens of lawsuits failed in courts across the country, they said.