A Fox News channel sign is seen at the News Corporation building in the Manhattan borough of New York City, New York
A Fox News channel sign is seen at the News Corporation building in the Manhattan borough of New York City, New York, U.S., June 15, 2018. Reuters

Fox knew that debunked theories about vote-rigging claims it broadcast were "total bs," according to election technology company Dominion Voting Systems in a filing made public in Delaware Superior Court Thursday, part of its $1.6 billion defamation lawsuit against the media giant.

"From the top down, Fox knew 'the dominion stuff' was 'total bs,'" Dominion wrote in its filing. "Yet despite knowing the truth--or at minimum, recklessly disregarding that truth--Fox spread and endorsed these 'outlandish voter fraud claims' about Dominion even as it internally recognized the lies as 'crazy,' 'absurd,' and 'shockingly reckless.'"

Dominion sued Fox News Networks in March 2021, alleging that the cable TV network amplified false claims that Dominion machines were used to rig the 2020 U.S. presidential election against Republican Donald Trump and in favor of his Democratic rival Joe Biden, who won the election.

Fox has argued that it had a right to report on election-fraud allegations made by Trump and his lawyers, and that Dominion's lawsuit would stifle freedom of the press.

"The core of this case remains about freedom of the press and freedom of speech, which are fundamental rights afforded by the Constitution and protected by New York Times v. Sullivan," a Fox spokesperson said in a statement.

Dominion filed suit against parent company Fox Corp in November 2021; the case was consolidated in December.

As part of discovery, Dominion has sought communications from Fox Corp Chairman Rupert Murdoch, his son, Fox Corp Chief Executive Officer Lachlan Murdoch, and Fox News personnel as it seeks to prove that the network either knew the statements it aired were false or recklessly disregarded their accuracy. That is the standard of "actual malice" that public figures must prove to prevail in defamation cases.

"The heart of this is really going to be whether there was false information put on the air, and whether they knew it was false or whether they were reckless in putting it on the air," said Roy Gutterman, director of the Newhouse School's Tully Center for Free Speech at Syracuse University.

Dominion alleged in its lawsuit that Fox amplified the false theories to boost its ratings and stay abreast of hard-right competitors including One America News Network, which Dominion is also suing. The complaint cited instances in which Trump allies like Rudy Giuliani and Sidney Powell appeared on Fox News and falsely claimed Dominion software may have manipulated vote counts in favor of Biden.

Thursday's filing reflects the outcome of months of discovery from both sides. Dominion in January questioned Fox Chairman Rupert Murdoch under oath, the most high-profile figure to face questioning in the case.

Earlier on Thursday, Fox filed a counterclaim in Delaware Superior Court, alleging that Dominion has no evidence to support its "staggering" damages claim.

A five-week trial in the case is scheduled to begin on April 17.