President Trump’s campaign sued The Washington Post for defamation Tuesday over two opinion columns published last year that alleged a connection between the campaign and Russian election interference.

The campaign sued the New York Times last week for another opinion column that had asserted such ties.

Legal experts say Trump stands little chance of prevailing in court in either case because libel laws extend a high degree of protection to published material about public figures and to opinion articles. Nevertheless, the campaign may be aiming to highlight its criticism of the mainstream media and to blunt suggestions that it colluded with Russian operatives.

The new lawsuit, filed in U.S. District Court in Washington, alleges that op-eds by Greg Sargent and Paul Waldman were false and defamatory.

Sargent’s June 13 column was titled “Trump just invited another Russian attack. Mitch McConnell is making one more likely.” The lawsuit contends that it was defamatory because it contained a claim that special counsel Robert S. Mueller III concluded that the campaign “tried to conspire with” Russia in a “sweeping and systematic” attack during the 2016 election.

Waldman raised a similar issue in his column published June 20, writing, “Who knows what sort of aid Russia and North Korea will give to the Trump campaign, now that he has invited them to offer their assistance?” The campaign said that statement was false and defamatory because it is “not seeking Russia’s or North Korea’s help in the 2020 election.”

Mueller’s report chronicled dozens of contacts between the Trump campaign and Russian nationals, as well as 10 instances of potential obstruction by Trump. Mueller testified last year that his investigation focused on whether campaign officials took part in a criminal conspiracy. He concluded that the evidence was insufficient to bring criminal charges.

Trump has repeatedly criticized The Post and its owner, Amazon founder and chief executive Jeff Bezos. At one point during the 2016 campaign, Trump barred The Post’s reporters from covering his events.

A division of Amazon, Amazon Web Services (AWS), is locked in a legal dispute with the Defense Department over the awarding of a $10 billion Pentagon cloud-computing contract to Microsoft. The company asserts that Trump interfered in the contracting process to exclude AWS, a claim backed up by former defense secretary Jim Mattis’ speechwriter in a recent book. (Mattis has denied making any comment.)

The Trump campaign’s lawsuit says the articles in question are “part of the The Post’s systematic pattern of bias against the Campaign, designed to maliciously interfere with and damage its reputation and ultimately cause the organization to fail.”

“It’s disappointing to see the president’s campaign committee resorting to these types of tactics, and we will vigorously defend this case,” said Post spokeswoman Kris Coratti.

The campaign is represented by attorney Charles Harder, who sued the website Gawker on behalf of pro wrestler Hulk Hogan, winning a $140 million judgment in 2016 that bankrupted the site and led to its sale. Harder also represented Melania Trump in lawsuits against the Daily Mail and a Maryland blogger who asserted that her former modeling agency had acted as an escort service. The first lady settled those suits after the plaintiffs agreed to compensate her.

Libel standards in the United States make it “virtually impossible” for Trump to win his cases against The Post and the Times, said RonNell Andersen Jones, a law professor at the University of Utah who specializes in media law. Public figures such as the president must prove that a publication knew a statement was false before it published it, a difficult standard to prove. What’s more, opinions about the conduct of public officials are given wide protection to encourage robust discussion.

“The suit is less a legitimate effort to seek legal redress and more a publicity measure designed to generate disdain for the media amongst a base that is already quite inclined to vilify the press,” Jones said Tuesday.

She added: “Trump and his lawyers of course do not believe they can win a libel suit over an opinion column discussing one of the major domestic and foreign relations issues of our day. What they believe is that they can use the suit to continue their own narrative about Russian interference and to compound the attacks on the press that they have made so central to their administration.”

A previous version of this story said that former Secretary of Defense James Mattis claimed President Trump interfered in the contracting process between Amazon Web Services and the Defense Department. The claim was made by Mattis’ former speechwriter, Guy Snodgrass, in a recent book, not by Mattis himself.