Donald Trump frequently takes swipes at the media — his most recent target is The New York Times after it published pages from his 1995 tax return — but what separates his gripes from those of other presidential contenders is that they often contain the prospect of legal threat.

Trump’s campaign claims the tax return was “illegally obtained.” The Times says it received it from an anonymous source with a return address at Trump Tower.

Even before this latest imbroglio, Trump tweeted that his lawyers “want to sue the failing @nytimes so badly for irresponsible intent. I said no (for now), but they are watching. Really disgusting.”

He didn’t specify a particular story or what “irresponsible intent” means. But the tweet carried a hint of libel litigation.

It might sound outrageous for a presidential candidate, president elect, or even a sitting president to file a suit against a media outlet. But Trump has a long history of litigation and of pursuing grievances even to an absurd degree. It’s not implausible that he’d actually go ahead and make a legal claim.

“Candidates for office do sue — every so often I see a state court case,” notes Eugene Volokh, professor at UCLA School of Law. However, he adds, lawsuits at the federal level are unusual. “At the presidential level — no, it is not done,” he says. “Filing a libel lawsuit is a real burden for the plaintiff, even for plaintiffs who are completely in the right.”

First Amendment attorney Floyd Abrams notes that, legally, Trump is already a public figure. “As president, he would be a public official, but the law is the same as to both,” he says. Abrams doesn’t see Trump’s contentious relationship with the media improving if he were to be elected. “I don’t think there is any reason to believe he would handle it any differently than he handles it now. He is who he is.”

On “The O’Reilly Factor” recently, Trump pointed to a New York Times story from May headlined “Crossing the Line: How Donald Trump Behaved With Women in Private.” Trump called the story false. “And honestly,” he added, “we’re going to take that up with them at a little later date. We’ll get rid of this first. We will go through this little process first, which I think is going to end very successfully on Nov. 8.”

The possibility of Trump actually succeeding in a libel suit is slim. He would have to prove actual malice: the fact that the journalists knew what they wrote was false or had reckless disregard for the truth. Additionally, from a practical standpoint, he would need to endure a discovery process that could be time-consuming and embarrassing. A legal action for the Times story would raise the prospect of dredging up all of the incidents described, point by point.

“One of the reasons people don’t bring libel suits is not just the legal challenges, but the intrusive nature of the discovery process,” Abrams notes.

Trump has said he would like to “open up” libel laws, making it easier for plaintiffs to pursue their claims. “We’re going to have people sue you like you’ve never got sued before,” he said, referring to the media at a February rally in Fort Worth, Texas.

The prospect of that threat becoming a reality is, to put it mildly, a long shot. Libel laws are determined at the state level but governed by a 52-year-old Supreme Court precedent. “There is quite literally no role for an American president to open libel laws other than urging the adoption of a constitutional amendment,” Abrams says.

Yet Trump’s statements have stirred alarm from progressive groups like People for the American Way as assaults on the First Amendment. Trump’s restrictions on reporters from certain news outlets covering his campaign events brought condemnation from the Reporters Committee for Freedom of the Press. Those bans, which included The Washington Post and Politico, have since been lifted, but the criticism of Trump’s perceived abuse of the First Amendment continues.

“The idea of a candidate for public office threatening to use our tort system as a means for inhibiting critique goes against the values that the First Amendment of the Constitution protects — robust debate and free exchange of ideas, especially in the context of national electoral politics,” Rebecca Brown, professor at USC’s Gould School of Law, writes via email.

Unusual as it would be for a presidential candidate to threaten legal action against the press, it’s not unprecedented. Barry Goldwater filed a libel suit in 1965 against Fact magazine over a story it published during the previous year’s campaign, in which the editors polled 12,356 psychiatrists to support a thesis that Goldwater was mentally ill. Goldwater won his suit — and the Supreme Court refused to take the case on appeal.

Trump, in fact, does have a history of pursuing libel litigation, despite the high hurdles of winning as a public figure. In 2005, he sued Timothy O’Brien over the book “TrumpNation,” in which O’Brien cited sources who estimated Trump’s net worth as much lower than the businessman claimed. O’Brien won on summary judgment.

In 2013, Trump filed a rather novel lawsuit against Bill Maher, who had said on “The Tonight Show With Jay Leno” that he would offer $5 million to Trump’s favorite charity if Trump could prove that he was not the “spawn” of an orangutan. Trump filed not a libel suit but a breach-of-contract suit, saying he had produced a birth certificate and demanding that Maher come up with the sum. Trump withdrew the suit before it went much further.

More recently, Trump’s wife, Melania, sued Mail Media, parent of U.K. newspaper Daily Mail, and a Maryland blogger for publishing claims that she once worked as an escort. After the suit was filed, Daily Mail retracted its story, even though it noted that the article had “stated that there was no support for the allegations.”

James Sammataro, managing partner at Stroock & Stroock’s Miami office, who represented Lee Daniels after Sean Penn filed a defamation claim against him, says the timing of Melania Trump’s suit “appears calculated to force publications to make a cost-benefit analysis before running any additional articles regarding Ms. Trump’s purported past — particularly during the remaining election cycle.”

Melania Trump hired attorney Charles Harder, who represented Hulk Hogan in his successful privacy lawsuit against Gawker Media. Her suit was filed in Maryland; a later claim was filed in the U.K., where plaintiffs may face a lesser burden in proving libel. Harder declined to comment on the timing of the Trump suit, citing attorney/client privilege, but said the case is “not hard to prove, whether it is in the U.S. or Britain.”

Sammataro believes the rationale is clear.  “The initial reaction is likely, ‘Why invite scrutiny now, during the most media-intensive period of the election cycle?’ Yet, with a little reflection, it seems clear that the objective is to cause all writers some pause over the next several months without the risk of any negative litigation details being leaked, as discovery will not occur until long after the election has been decided.”

As much as Trump has railed against the media, a Hillary Clinton presidency would hardly bring bliss to the White House’s relationship with journalists.

The current administration’s relationship with the White House press corps has often been acrimonious, and Clinton’s default seems to be one of not quite trusting the Fourth Estate.

She famously railed against the “vast right-wing conspiracy” in 1998, and during this campaign, she has expressed frustration at her press coverage.

“She is just naturally distrustful of the media, and she has been that way for a long time,” says Frank Sesno, the former CNN anchor, White House correspondent, and Washington bureau chief who is now director of the School of Media and Public Affairs at George Washington University.

While Clinton “can surprise people,” he says, “her administration could have a very complex relationship with the media that could bring a lot of baggage from day one.”

Meanwhile, were Trump to win, he “will think that he has mastered the media, that he used his force of personality and his persistent online presence and Twitter to set the agenda, to manipulate and prompt the media to follow him,” Sesno says.

As much as that may embolden him, Trump would still run into the reality of the White House press corps, a 24/7 machine where the focus is constantly on who is up and who is down.

Presidents, Sesno says, “love to shoot the messenger. … But they also know there’s a line they don’t cross. Because, at the end of the day, the messenger matters.”

That is particularly true when a crisis hits, and the occupant of the Oval Office needs a measure of credibility to reassure the public.

“Every time a president really has a crisis,” Sesno says, “if that reservoir of credibility is low to empty, there isn’t much water to drink.”