A group has put out a new ad on TV about Donald Trump and his incompetent response to the pandemic, contrasting his various statements with the reality.

The Trump campaign does not like the ad and is suing to get it removed from the airwaves. Mark Joseph Stern writes that these lawsuits will undoubtedly fail but the point is not to win but to intimidate TV stations with the cost of defending themselves.

The possibility of a lawsuit is a more substantial menace. Trump’s campaign accuses stations of broadcasting “false information” and reserves its right “to pursue all legal remedies available.” That translates to a defamation suit. Stations will have to devote significant time, resources, and money to fight off any legal action, but they will probably prevail. The First Amendment was designed to safeguard political speech. It requires public officials to prove that their critics knowingly lied, or acted with reckless disregard for the truth, to win defamation suits. The Supreme Court has even granted constitutional protections to outright lies, holding that an “interest in truthful discourse alone” is not “sufficient to sustain a ban on speech.” Following SCOTUS’s lead, lower courts have invalidated state laws that penalize knowingly false statements made by political campaigns.

Put simply, politicians and their allies have a First Amendment right to stretch the truth when smearing their opponents, and this right also shields outlets that carry their smears. If the Trump campaign does sue broadcast stations for airing Priorities USA’s ad, it will, in all likelihood, lose. It would lose even if the ad peddled an outright falsehood rather than a tendentious recitation of the facts. But its suit would still compel stations to spend sums of money defending themselves in court.

And therein lies the true danger here: not that stations will actually lose in court, but that they grow so afraid of legal action that they self-censor. Trump is already trying to scare reporters out of covering him accurately; he has threatened to sue several news organizations, including CNN, and his campaign filed a frivolous libel suit against the New York Times. Media outlets are already on alert that Trump might draw them into expensive legal battles. In light of Wednesday’s letter, TV stations are also now aware of that risk. They may refuse to run ads that contain factually debatable criticisms of the president for fear of a costly lawsuit. Meanwhile, they will all continue to give airtime to the president’s incessant lies, because they are newsworthy. Trump can use the power of the pulpit to tilt the playing field in his favor. He could successfully monopolize the marketplace of ideas in the midst of his reelection campaign.

The Trump campaign’s cease-and-desist letter closes on a note of unintentional comedy, declaring that “we will not stand idly by and allow you to broadcast false, deceptive, and misleading information concerning President’s Trump’s healthcare positions without consequence.” In fact, no one lies about Trump’s “healthcare positions” more than Trump himself: The president routinely pretends to support protections for preexisting conditions that his administration is currently fighting to overturn. If TV stations could not broadcast false claims, they would never air a single Trump speech. For better or worse, Trump has a right to manipulate the truth to his political advantage. What he cannot do is gag his opponents when they try to punch back in kind.

People with deep pockets often sue just to financially ruin the defendant even if the latter wins the case. This can often lead to an insidious form of self-censorship.