“Police officers conduct approximately 29,000 arrests every day,” Chief Justice John Roberts noted in his opinion in Nieves v. Bartlett, an important First Amendment case decided last Monday. That’s roughly the population of Georgia cuffed and stuffed on an annual basis.

One might think that many arrests is too many. One might wonder about the degree to which factors such as race, immigration status, and wealth contribute to individual arrests. One might even wonder about the percentage of cases in which the power to arrest is abused.

America’s chief justice, however, worries more about the overworked police than about the people they arrest. Arresting that many folks is “a dangerous task that requires making quick decisions,” he wrote—so many people, so little time. It is thus the job of the Court “to ensure that officers may go about their work without undue apprehension of being sued.”

If that’s the appropriate aim for an Article III court, Nieves will help achieve it; the decision will make it harder to hold officers to account when they—as we all know they sometimes do—arrest citizens in retaliation for speech they don’t like. It can occur in a political-protest situation or simply during everyday dealings between police and people. Police—not all, but some—can be quick to cuff a nettlesome protester, an officious onlooker with a cellphone camera, or a mouthy suspect. The law of the First Amendment is clear: An individual should not face official retaliation for engaging in “protected speech” alone, even when that speech is unpleasant or hostile. “Retaliatory arrest” is a recognized federal cause of action.

Garrett Epps: Can police retaliate against loudmouths?

Of course, police seldom charge anyone with “engaging in protected speech to which I object.” The charge is often something like “disorderly conduct” or “failure to obey a lawful order.” Sometimes people really are guilty of those offenses; sometimes people weren’t engaging in speech activities at all, but later claim they were. But sometimes people incur the disapproval of a cop for reasons other than those charged.

How does the law sort them out?

Arrests are supposed to be based on something called “probable cause”—which means a “reasonable ground to suspect that a person has committed or is committing a crime.” The police officer must have information at the time suggesting that possibility.

Police agencies argue that, if the officer has probable cause to arrest, the First Amendment issue should be irrelevant. That would allow a lot of First Amendment abuse. Over the years, the Supreme Court has made clear that police can arrest citizens for virtually any offense, down to driving without fastening a seat belt. Most people can’t go through a day without committing one—or more than one—crime, including crimes they haven’t heard of. What happens when a citizen claims that an officer has arrested him or her because of First Amendment speech?

Roberts joined with four other members of the Court to provide an answer: If the officer has probable cause, then his First Amendment motivation is irrelevant—unless the plaintiff presents “objective evidence that he was arrested when otherwise similarly situated individuals not engaged in the same sort of protected speech had not been.”

In other words, if you cheese off an officer by bad-mouthing the mayor (or the cop), you can be arrested if there is probable cause you did something wrong. And you can’t sue for “retaliatory arrest” unless either the arrest is for an offense such as “spitting on the sidewalk” or “affray,” which police virtually never use, or a hundred people are doing the same thing and only the ones engaged in protected speech were arrested. The burden will be on you to prove that the charge is rare—or that others were doing exactly the same thing at the same place and time and weren’t arrested. (I suspect that many courts will require proof that it really was exactly the same thing.)

After that, you have the burden to show that the “expressive activity” (speech, picketing, carrying a sign, etc.) was the real cause of the arrest. The “causation” element is hard, since you have to prove the officer’s state of mind. Officers sometimes tell you their motivation, in remarks such as “You can’t talk that way about our military.” But (surprise!) it turns out those won’t help you, because Roberts has modified his rule thus: “Because this inquiry is objective, the statements and motivations of the arresting officer are ‘irrelevant.’” Some other evidence is needed, or the case will be dismissed before trial.

Read: John Roberts’s biggest test is yet to come

Roberts is a master of the seemingly plausible distinction that in fact makes little sense. What is not “objective” about the officer’s own words? Aren’t they, in fact, the best evidence available of motivation? I suspect the thought behind this is that it’s too easy to allege that the officer said something when there’s no one around to confirm or deny. (“And then he said to me, he said, ‘There’s no one around us right now, Professor Epps, so allow me to admit that I object to your view of interpleader under Rule 22(a)(2) but in order to conceal my unconstitutional motivation, I am going to charge you with disorderly conduct instead.”) But surely that problem could be dealt with simply by requiring a plaintiff to plead something more than bare allegations.

As Justice Sonia Sotomayor pointed out in her solo dissent, arrests are usually documented in police reports, and more and more often they are recorded on video by police body cameras, news film crews, and curious onlookers. That evidence seems to me worth considering—unless the real purpose of the Roberts rule is to provide all but complete immunity to police, a result made more palatable by the kind of pseudo-plausible car-salesman patter of which Roberts is the Court’s unchallenged master.

The old legal adage claims that “hard cases make bad law.” More and more I think hard cases are good—they require both lawyers and judges to be exact about their facts and their legal theories. It is the easy case that tempts courts to sloppiness. Nieves v. Bartlett is an easy case, and the Court majority has used it to affect a lot of hard ones.

This case is easy because as the Court reviewed the facts alleged, the police officer should win. The challenged offense occurred at Alaska’s annual Arctic Man, once described by the journalist Matt White as “a weeklong, booze and fossil-fueled Sledneck Revival bookended around the world’s craziest ski race.” It’s held in a remote location northeast of Anchorage, and policed—gingerly—by a vastly outnumbered crew of state police.

During a drunken revelry at Arctic Man 2014, Sergeant Luis Nieves approached a group of merrymakers to ask them to move their beer keg. Russell Bartlett, one of the merrymakers, objected to this approach, and when Nieves tried to talk to Bartlett further, he refused to talk to the sergeant.

Bartlett had a right to do that; ordinary people do not have to talk to police if they choose not to.

Not long afterward, another trooper, Bryce Weight, was questioning other, underage celebrants about alcohol use when Bartlett approached and told Weight to leave the kids alone. By this time, it’s pretty clear that Bartlett was a bit the worse for malt beverages. He was also standing nose to nose with the lawman. Weight stiff-armed Bartlett away from his personal space—at which point Nieves came over and arrested Bartlett.

Bartlett testified later that once he was cuffed, Nieves taunted him: “Bet you wish you would have talked to me now.”

Garrett Epps: Will John Roberts block the triumph of legal conservatism?

This is, as Justice Ruth Bader Ginsburg noted in a separate concurrence that is in effect a dissent, a “thin case.” There’s no additional evidence that Nieves made the admission—complete news footage of the confrontation did not survive. As Ginsburg wrote, there is “some evidence of animus … but perhaps not enough to survive summary judgment.” Had the Court majority wished to erect a heightened-evidence standard, it could have done so; instead, it came up with a rule whose nod to the First Amendment is cursory at best.

Indeed, so dismissive is the majority of the rights of citizens that Justice Neil Gorsuch declined to join, instead writing a characteristically ponderous nine-page opinion concurring in part and dissenting in part. Oddly, he situates this drunken free-for-all in the context of the struggle against a heartless administrative state rather than harried troopers in the wilderness:

History shows that governments sometimes seek to regulate our lives finely, acutely, thoroughly, and exhaustively. In our own time and place, criminal laws have grown so exuberantly and come to cover so much previously innocent conduct that almost anyone can be arrested for something. If the state could use those laws not for their intended purposes but to silence those who voice unpopular ideas, little would be left of our First Amendment liberties, and little would separate us from the tyrannies of the past or the malignant fiefdoms of our own age.

Gorsuch points out that a “probable cause is enough” rule would target only police who make completely illegal arrests. But “retaliatory arrest” suits are designed to “guard against officers who abuse their authority by making an otherwise lawful arrest for an unconstitutional reason.” The opinion suggests that probable cause should be a factual element for the jury to consider, not an almost-absolute bar to getting a case to that jury in the first place.

Sotomayor wrote a full-throated dissent. The new rule, she wrote, defies precedent. The Court already has a venerable test for First Amendment retaliation in other contexts (such as, for example, disciplinary action against dissenting government employees). It’s called the Mt. Healthy test and comes in two parts. First, can the plaintiff show that the protected speech was a “‘substantial’ or ‘motivating’” factor” in what happened to him? If so, then the burden shifts to the government to show that it would have (not, as in a test for “probable cause,” could have) taken the same action even without the protected speech. Barring the evidence of what a police officer says makes no sense, she argued, and “risks licensing even clear-cut abuses.” The result “shortchanges [the First Amendment] in the name of marginal convenience.”

Roberts’s test comes to our constitutional doctrine more or less out of thin air. The chief justice, a First Amendment tiger when the rights of rich campaign donors are at issue, clearly frets that ordinary people—protesters, let’s say randomly—will bother hardworking police. Remarkably enough, Roberts gathered five votes for his invented rule—his own plus those of Justices Stephen Breyer, Samuel Alito, Elena Kagan, and Brett Kavanaugh. The accession of Breyer and Kagan should underline an important truth about this court—that the “four liberals” shorthand disguises that two of the four are very, very moderate indeed on many issues.