(NewsNation) — A trial that could alter the future of television news and defamation lawsuits in the U.S. is set to begin Tuesday.

Dominion Voting Systems is suing Fox News Network for $1.6 billion after it says the media organization knowingly aired false information about the 2020 election in an effort to boost ratings.

The voting machine company claims its reputation was damaged after allies of former President Donald Trump went on the cable network and accused the company of rigging the election against him.

The jury trial is scheduled to begin on April 18 and is expected last about a month. The trial was originally planned to start April 17, but the judge delayed the case without explanation.

What is the trial about?

Dominion has accused Fox News of knowingly spreading false claims about its ballot-counting machines which many Trump supporters blamed for his 2020 election loss.

The unfounded accusations of rigged voting machines from Trump allies cost the company tens of millions in lost contracts and reputational damage, Dominion alleged in court documents.

One expert, in a report submitted by Dominion in November, estimated the company had suffered more than $72 million in lost opportunities as a result of the misinformation. The same expert estimated the company experienced a $920 million decline in overall value.

In order to win the case, the Denver-based voting machine company will have to prove Fox acted with “actual malice,” which means the network knowingly spread false information or recklessly disregarded the truth, according to American libel law.

Why was the trial delayed?

Superior Court Judge Eric Davis said Sunday that the trial would be pushed back one day to April 18, but did not give a reason why. According to multiple media outlets, Fox is seeking a possible settlement but so far no deal has been announced.

Davis said the delay was not “not unusual.”

Now, the trial is set to begin on Tuesday at 9 a.m. ET.

What have we learned so far?

Documents related to the lawsuit show a stark contrast between the 2020 election narrative Fox News presented to viewers versus the private opinions of its own stars.

Text exchanges between hosts Tucker Carlson and Laura Ingraham cited in court documents showed the two doubted claims of election fraud even as their primetime coverage continued to platform 2020 election deniers.

“Sidney Powell is lying” about having evidence for election fraud, Carlson said via text on Nov. 16, 2020 to a Fox News producer.

In a separate instance, Ingraham texted Carlson that Powell — who was one of Trump’s lawyers — is “a complete nut. No one will work with her. Ditto with Rudy,” referring to the former New York mayor and Trump supporter Rudy Giuliani.

How has Fox responded?

Fox has maintained that it was covering allegations that were newsworthy and protected by the First Amendment. The network has disputed Dominion’s value and said it could not have suffered the $1.6 billion in damages the company is seeking.

“The case has no merit, and the outrageous damage claim only highlights its naked attempt to suppress legitimate speech protected by our Constitution,” Fox said in a statement.

How difficult are these cases to prove?

It is notoriously difficult to prove libel in the American legal system, largely due to a 1964 Supreme Court decision.

In New York Times v. Sullivan, the court adopted a higher standard for public officials to prove defamation of character. Since then, plaintiffs have had to show that a defendant acted with “actual malice,” which means proving a news organization published false statements is not enough to win a case on its own.

Judge Davis has already concluded that none of the election fraud allegations made by Trump allies against Dominion were true. The key question before the jury is whether Fox deliberately aired those falsehoods despite knowing they were untrue.

Fox News has said the case is ultimately about “the First Amendment protections of the media’s absolute need to cover the news.”

Dominion has said it believes in the First Amendment but argues “it does not shield broadcasters that knowingly or recklessly spread lies.”

What’s at stake?

The trial could prove to be a landmark case that alters the trajectory of news organizations and defamation lawsuits in the United States.

If Fox News lawyers are able to prove the network was simply covering newsworthy, albeit false, allegations, it would mark a continuation of the broad protections news organizations have to publish content as they see fit.

Some First Amendment lawyers have argued that a Fox victory could fuel the argument that the bar for defamation has been set too high, which could ultimately embolden efforts to roll back other protections for journalists.

On the other side, if Dominion prevails it could open the door for additional lawsuits against other news organizations. Those same organizations, many of whom have embraced and benefitted from the transition to opinion news, would be forced to consider their legal liability moving forward.

Former Fox News anchor Bill O’Reilly thinks the trial could be “catastrophic” for the most-watched cable news network in the country.

“Their core audience will stay with them no matter what happens but they’ve lost the younger audience, the 25 to 54 audience,” O’Reilly said Wednesday.

Who will testify?

Fox News hosts Tucker Carlson, Sean Hannity and Maria Bartiromo are all expected to testify at the trial. The cable news stars are among 11 people the network intends to make available, according to a recent court filing. Host Jeanine Pirro and former host Lou Dobbs were also on Fox’s witness list.

Rupert Murdoch could also take the stand. Last week, Judge Davis determined the 92-year-old media mogul and his son Lachlan Murdoch could be called to testify even though they were not on the Fox witness list.

“They’re not used to be being pushed back on or cross-examined, so it will be really interesting to see how they address questions and push back,” NewsNation media contributor Colby Hall said last week. “We could see some frustration, especially when it comes to Rupert Murdoch and Lachlan Murdoch.”

Davis said Fox board member Paul Ryan, a former Republican speaker of the U.S. House of Representatives, could also be summoned via a trial subpoena.

In an email to Reuters, a Fox News rep accused Dominion of “demanding witnesses who had nothing to do with the challenged broadcasts” as part of “their political crusade in search of a financial windfall.”