Fox News Media, the Rupert Murdoch-controlled cable group, filed a motion on Tuesday to dismiss a $1.6 billion defamation lawsuit brought against it in March by Dominion Voting Systems, an election technology company that accused Fox News of propagating lies that ruined its reputation after the 2020 presidential election.

The Dominion lawsuit, along with a similar defamation claim brought in February by another election company, Smartmatic, have been widely viewed as test cases in a growing legal effort to battle disinformation in the news media. And it is another byproduct of former President Donald J. Trump’s baseless attempts to undermine President Biden’s clear victory.

In a 61-page response filed in Delaware Superior Court, the Fox legal team argues that Dominion’s suit threatened the First Amendment powers of a news organization to chronicle and assess newsworthy claims in a high-stakes political contest.

“A free press must be able to report both sides of a story involving claims striking at the core of our democracy,” Fox says in the motion, “especially when those claims prompt numerous lawsuits, government investigations and election recounts.” The motion adds: “The American people deserved to know why President Trump refused to concede despite his apparent loss.”