In second impeachment, misinformation spreads at a lower intensity.

Misinformation about the second impeachment trial against former President Donald J. Trump is swirling online at a much slower clip than the first impeachment trial against him — at least so far.

The media insights company Zignal Labs collected misinformation narratives around the impeachment proceedings from Jan. 25 to Feb. 9, and found three emerging falsehoods that had gotten thousands of mentions on social media and cable television and in print and online news outlets.

The falsehoods, though, had not gained as much traction as misinformation about Mr. Trump’s first impeachment trial or the outcome of the 2020 election. Still, the data shows how virtually any news event is an opportunity to spread lies and push divisive rumors, helped along by social media algorithms, eager audiences and a broken fact-checking system.

Here are the three most popular misinformation narratives about the impeachment proceedings.

Nancy Pelosi is responsible for the Capitol attack: 30,300 mentions

The falsehood that Congresswoman Nancy Pelosi somehow knew that a mob would storm the Capitol and is using the impeachment trial as a “diversion” effort was amplified by Senator Ron Johnson on Fox News on Feb. 7.

“We now know that 45 Republican senators believe it’s unconstitutional,” Mr. Johnson said on Fox News, referring to the impeachment proceedings. “Is this another diversion operation? Is this meant to deflect away from what the speaker knew and when she knew it? I don’t know, but I’m suspicious.”

A video clip of the interview was viewed at least 2.1 million times on Twitter.

The attack on the Capitol was preplanned, undercutting the basis of the impeachment trial: 8,135 mentions

The falsehood that the Capitol attack was preplanned and “undercuts Trump impeachment premise” gained traction on Feb. 8 when a conservative outlet called Just the News published an article detailing the claim. The article was shared 7,400 times on Twitter and at least 3,000 times on Facebook.

The founder of Just the News, John Solomon — a Washington-based media personality who was instrumental in pushing falsehoods about the Bidens and Ukraine — shared the falsehood from his own Twitter account, collecting thousands of likes and retweets. Other Twitter users then picked up the rumor, further amplifying the false narrative.

Focusing on what was planned in advance should have no bearing on the impeachment trial itself, according to 144 constitutional law scholars who submitted a written analysis of the case against Mr. Trump. They said many of them believe that “President Trump can be convicted and disqualified because he is accused of violating his oath through an ‘extraordinary, unprecedented repudiation of the president’s duties to protect the government’ through his ‘further acts and omissions after he incited the crowd to attack the Capitol.’”

Renewed calls to impeach Obama over ‘spying on Trump’: 5,017 mentions

The narrative that it is not too late to impeach former President Barack Obama started to gain traction on Jan. 26 on Twitter. Thousands of Twitter users shared an old suggestion from Representative Matt Gaetz, a Florida Republican, that if a former president can be impeached, Mr. Obama should be tried for spying on Trump.

The false narrative was a revival of “Spygate” — a labyrinthine conspiracy theory involving unproven allegations about a clandestine Democratic plot to spy on Mr. Trump’s 2016 campaign. But the theory fizzled as the past four years saw none of Mr. Trump’s political enemies charged with crimes. And in 2019, a highly anticipated Justice Department inspector general’s report found no evidence of a politicized plot to spy on the Trump campaign.