Today in Mahanoy Area School District v. B.L., the Supreme Court ruled 8–1 that a public school violated the First Amendment when it punished a student for her salty Snapchat story. The Court’s ruling sends a clear message to public schools that punishment of off-campus speech will rarely be justified. Unfortunately, however, the Court declined to establish any bright-line rules for the regulation of off-campus student speech, meaning students did not receive as much clarity or security as they could have.

This case began when B.L., a rising high school sophomore at a Pennsylvania public school, didn’t make the varsity cheerleading team. At a local hangout off-campus, she took to Snapchat to voice her frustrations and posted a picture of herself and a friend holding up their middle fingers, adding a caption with some F‐​bombs. When the picture was brought to the attention of her cheer coaches, B.L. was suspended from the junior varsity cheerleading team for the year.

The key issue in this case was the scope of the rule established in Tinker v. Des Moines (1969), which held that public schools can regulate student speech that would “materially and substantially disrupt the work and discipline of the school.” The Third Circuit below ruled for B.L. and established a bright-line rule that Tinker’s “substantial disruption” test does not apply to off-campus speech like B.L.’s use of social media.

The Supreme Court affirmed the Third Circuit’s judgment that the punishment was unconstitutional, but it did not affirm the Third Circuit’s categorical rule. Instead, in an opinion by Justice Breyer (who is often fond of multi-factor balancing tests rather than bright-line rules), the Court opted to provide only general guidelines for how lower courts should approach off-campus speech cases in the future.

First, the Court declined to foreclose the application of Tinker to off-campus speech in every instance, holding that the reasons justifying Tinker do not “always disappear when a school regulates speech that takes place off campus.” The court suggested, without limiting itself to the examples offered, that some circumstances potentially calling for regulation of off-campus speech might include bullying classmates, threats aimed at teachers or other students, cheating or otherwise breaking the rules on school assignments, and breaches of school security devices.

Then, in the crux of the opinion, the Court identified three features of off-campus speech that, in the Court’s words, “diminish the strength of the unique educational characteristics that might call for special First Amendment leeway” to regulate speech.

The first feature is that “off-campus speech will normally fall within the zone of parental, rather than school-related, responsibility.” (This point was emphasized in Cato’s amicus brief, which argued that off-campus speech should be left entirely to parents and, if necessary, law enforcement.)

The second feature is that, by definition, off-campus speech “include[s] all the speech a student utters during the full 24-hour day.” Regulating only on-campus means a student can wait to step off the school bus and then speak their piece. Regulating speech off-campus, by contrast, “may mean the student cannot engage in that kind of speech at all.” In the Court’s words, that means judges “must be more skeptical of a school’s efforts to regulate off-campus speech.” And this skepticism should be ratcheted up even further when political or religious speech is at issue, at which point courts should impose “a heavy burden to justify intervention.”

And the third and final feature is that public schools have an “interest in protecting a student’s unpopular expression.” In other words, the mere fact that speech is unpopular with other classmates is not a justification for schools to restrict it; if anything, it’s a reason why schools should be especially vigilant to protect it.

Applying these guidelines to the facts at hand, the Court easily found that the school was not justified in punishing B.L.’s single Snap. Indeed, the Court strongly suggested that even if B.L. had said the same things on campus, it would not have met Tinker’s “substantial disruption” standard. Judge Thomas Ambro of the Third Circuit had concurred in the judgement below on those narrower grounds, and the Supreme Court today noted that its reasons “resembl[e] those of the [Third Circuit] panel’s concurring opinion.”

In a concurrence, Justice Alito (joined by Justice Gorsuch) stressed that public schools only have the right to regulate student speech to the extent that parents have impliedly consented to that regulation by enrolling their children. Alito stressed that such implied consent is much less likely for off-campus contexts, where parents themselves retain control and supervision of their students.

In a solo dissent, Justice Thomas argued that the Court’s student speech doctrine, going all the way back to Tinker, is not consistent with the original understanding of the First Amendment. Thomas argued that the right of schools to regulate students in place of their parents (in loco parentis) was an accepted doctrine at the time of the founding with few limitations, and that the First Amendment was not understood to create any such limitation on that doctrine.

Overall, Mahanoy is a win for student speech; it should not go unappreciated that this is the first time since Tinker that the Supreme Court has actually invalidated a school’s punishment of student speech. Going forward, the guidelines that the Court established mean that students speaking off campus should rarely have their speech curtailed. Nonetheless, the hesitancy of the Court to establish any bright-line rule, not even that regulating off-campus political speech is categorically out of bounds, is disappointing. As the Court has recognized in other contexts, bright-line rules avoid the chilling effect that can come from uncertainty and the remote possibility that speech might be punished. While today’s opinion provides public school students many reassurances, it doesn’t provide them any certainties.