Right-wing activist group Project Veritas and its ex- leader have renounced bogus claims that a Pennsylvania postmaster illegally backdated mail-in ballots during the 2020 US election, highlighting the power of litigation in combatting disinformation even years later.

The organization and its founder James O'Keefe, known for sting operations targeting progressives, admitted in statements Monday they had helped broadcast the lie, after settling a defamation lawsuit brought by the postmaster.

The settlement is the latest in a string of such suits targeting those who intentionally spread lies about the 2020 US presidential election.

Project Veritas admitted to having amplified a mail carrier's claims that he overheard postmaster Robert Weisenbach discussing a scheme to illegally backdate late mail-in ballots, an allegation that the group spread in articles and videos published after the 2020 election.

"Neither Mr. Weisenbach nor any other USPS employee in Erie, Pennsylvania, engaged in election fraud or any other wrongdoing related to mail-in ballots," both of their statements said, adding that there is "no evidence" fraud occurred.

Previous defamation suits have forced similar retractions from Donald Trump's attorney Rudy Giuliani and others who parroted the ex-president's false claims about widespread fraud.

"The hope is that some of these defamation verdicts and settlements will play a role in deterring the spreading of election lies," said Rick Hasen, an election law expert at UCLA.

"They help show that people who try to undermine free and fair elections may pay a price."

The statements are also a reminder of the post-2020 chaos, which experts say could recur in 2024 as Trump eyes a rematch with President Joe Biden.

"We have seen new and often outlandish claims around every facet of the election process, from absentee voting by mail to the type of pens being used," said Tammy Patrick of the National Association of Election Officials. "I imagine that trend will continue."

'I was wrong'

A Pennsylvania court ruling in 2020 allowed ballots received within three days of Election Day to be counted if they were postmarked by that date.

Court filings say Weisenbach, a registered Republican, voted for Trump in 2020. But after being branded a "Trump hater" in the Project Veritas interview, he received death threats and was forced to temporarily flee his home, his lawyers said.

The mail carrier who initiated the claims that Weisenbach manipulated ballots, Richard Hopkins, now concedes he "only heard a fragment of the conversation and reached the conclusion that the conversation was related to nefarious behavior." 

Trump has previously praised Hopkins as "a brave patriot" for speaking out, and his campaign had cited the mail carrier's erroneous allegations in litigation aiming to block Pennsylvania from certifying its results. 

Lawmaker Lindsey Graham, top Republican on the Senate Judiciary Committee, also referenced the claims in a letter to the Justice Department calling for a federal investigation.

"As I have now learned, I was wrong," Hopkins said in a statement apologizing to Weisenbach, whom the US postal service inspector general cleared in a 2021 investigation.

A lawyer representing Project Veritas and O'Keefe did not respond to requests for comment. 

Weisenbach's attorney, David Houck, said the case was "resolved in a manner acceptable to all parties."

'Unfortunate reality'

The settlement comes after a jury in December ordered Giuliani, who spearheaded Trump's legal efforts to reverse the 2020 results, to pay $148 million in damages for defaming two Georgia poll workers with accusations of ballot tampering.

Giuliani still faces lawsuits from companies including Dominion Voting Systems, which secured a $787.5 million settlement from Fox News after suing over the network's false claims that its machines altered votes.

For Patrick, a former Arizona elections official, correcting the record is always important -- even years later.

"There are voters and members of the public who will only listen to -- will only believe -- the individuals who made these claims to begin with," she told AFP.

"The unfortunate reality of the situation is that the truth won't get the same airtime, the same distribution as the inflammatory statements."

Trump, who was indicted in August for his efforts to overturn Biden's 2020 victory, is already suggesting November's contest will be stolen.

"The radical left Democrats rigged the presidential election in 2020," he said last month at a rally in Nevada. "We're not going to allow them to rig the presidential election of 2024."