Updated March 29, 2023 at 11:39 AM ET

The Delaware judge overseeing a $1.6 billion defamation lawsuit against Fox News on Tuesday did not seem to buy the argument that founder Rupert Murdoch was too infirm to testify at trial next month.

The judge told Fox's attorneys not to make him "look like an idiot."

The remarks came at the outset of a pre-trial hearing when Judge Eric M. Davis noted that he previously had received a letter stating that the 92-year-old Murdoch "couldn't travel" to the trial in Delaware because of COVID.

"I also have people telling me that he's done some things recently that [show] he's hardly infirm," Davis said, noting that Murdoch had recently announced his engagement to be married for the fifth time and plans to travel between his homes in Los Angeles, Montana, New York and London.

The exchange was the first of several in which the normally impassive Davis warned Fox attorneys to "be careful."

It also foreshadowed a key contention in the widely watched defamation case brought by Dominion Voting Systems against Fox News: Were top executives, including controlling owner Murdoch, responsible for the broadcasting of baseless election fraud claims in late 2020?

Dominion intends to call not just Murdoch but a long list of Fox executives and stars to the stand. The list includes Murdoch's son Lachlan — the head of Fox News' parent company Fox Corp. — and hosts Tucker Carlson, Sean Hannity, Lou Dobbs and Maria Bartiromo.

It also includes Abby Grossberg, a senior producer for Carlson and Bartiromo who was fired last week after she claimed, in her own lawsuit against Fox, that the network was trying to pin the blame for the election-fraud falsehoods on her and other female employees, including Bartiromo.

Fox's live witness list is notably shorter, including some key executives and stars as well as officials at Dominion and the private-equity fund that partly owns it. It does not include the Murdochs.

Dominion attorneys allege the company suffered reputational harm after Fox — from individual hosts up to the C-suite — either encouraged or purposely turned a blind eye while false claims proliferated on the network – including claims that asserted the voting machine software company had engaged in a conspiracy to steal the 2020 election from then-President Donald Trump.

Fox attorneys deny the lawsuit's allegations on their face, arguing the network was airing newsworthy claims being made by an inherently newsworthy person — the sitting president — and his representatives in the wake of a heated election.

Officials from Fox said this week that Dominion had sought to limit the network's First Amendment arguments, pointing to sealed motions that Fox claims would limit its attorneys from referencing newsworthiness in the network's defense.

Yet Fox attorneys also specifically push back against Dominion's assertion that culpability could extend to the executives and board members of Fox Corp.

The case, which was filed last year, has so far uncovered thousands of documents that attorneys intend to use as trial exhibits and has prompted scores of depositions.

On Tuesday, Fox attorney Matthew Carter pointed to Murdoch's deposition when responding to Davis' incredulity about the media magnate's ability to travel.

Carter said there had been a miscommunication. He said his side hadn't argued that Murdoch was infirm, but that there was no reason for his trial testimony given that the Murdoch had already submitted to seven hours of questioning in the deposition.

In his deposition, Murdoch asserted that he knew Trump had lost the 2020 election, but certain Fox hosts, including Bartiromo and Dobbs, had "endorsed" the narrative of a stolen election.

He also acknowledged he had the power to dissuade Fox News' executives and stars from giving airtime to Trump attorney Rudy Giuliani, who peddled the lie.

"I could have," Murdoch said in his deposition. "But I didn't."

Ultimately, Davis indicated that he has the authority to compel Murdoch to appear in court at trial.

Debate over making emails, texts and legal documents public

Still unclear is whether Davis could do the same for officials farther down the Fox chain of command, including those directly involved in producing specific segments.

The attorneys at the Tuesday hearing sparred over that question and others, such as topics that could be covered during testimony, the type of exhibits that could be shown, and even the number of days of advance notification a witness must be given before their testimony.

The latter point frustrated the judge, whom has been described by Delaware attorneys as "Cool Hand Luke" for his demeanor.

"You guys are fighting over 24 hours?" Davis asked, again with near incredulity.

The hearing then turned to a hotly debated issue of the public disclosure of court documents. (Attorneys for NPR and other media organizations are challenging widespread redactions throughout the documents.)

Dominion attorneys said Fox has shown a pattern of attempting to shield documents from the public eye, stating its attorneys had even engaged in what could be "asymmetrical warfare" by objecting to their exhibits from being used in open court.

The statement again sparked an animated reaction from the judge who asked Fox if they really objected to "every single exhibit." Fox attorneys confirmed they had, to which Davis later said, "this isn't a game."

In response, an attorney for Fox said Dominion had created a massive undertaking for their side by including 1,000 more exhibits than her side had. Fox attorneys had objected to everything because they did not want to waive their right to object in the future.

"It's simply a matter of volume," she said.

As discussions continued, Davis told Fox 's attorneys for a final time to "be careful."

Fox attorney Katherine Mowery had argued the court should redact court documents about the network's fact-checking process that took place in its so-called "Brain Room."

As was the theme of the day, the judge showed skepticism, stating "those were used in my courtroom and I didn't seal the courtroom."

Further, he said his forthcoming opinion on separate motions from Dominion and from Fox to rule in their favor before trial would include mentions of the Brain Room.

"I'm not redacting my opinion." Davis said.

David Folkenflik contributed to this story.

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