The Seventh Circuit, in Nuxoll v. Indian Prairie School Dist. #204, just held that a student did have the right to wear such a T-shirt. (The student was wearing it in opposition to a pro-gay-rights National Day of Silence.)
The panel majority (Judge Posner joined by Judge Kanne) also opined, though, that under Tinker and Morse v. Frederick, the school would have broad rights to restrict shirts that were sufficiently derogatory of various groups, "if there is reason to think that a particular type of student speech will lead to a decline in students' test scores, an upsurge in truancy, or other symptoms of a sick school — symptoms therefore of substantial disruption." And the panel especially singled out speech that's derogatory to "highly sensitive personal-identity characteristics" as speech that seems especially likely to cause such disruption. The examples the majority gave as (apparently) restrictable were "blacks have lower IQs than whites," "a woman's place is in the home," "homosexuals are going to Hell," and "homophobes are closeted homosexuals"; it's not completely clear where the panel was committing itself to a conclusion that these particular statements would be restrictable, but that seems the likeliest interpretation.
As to "Be Happy, Not Gay," though, the majority concluded:
"Be Happy, Not Gay" is only tepidly negative; "derogatory" or "demeaning" seems too strong a characterization. As one would expect in a school the size of Neuqua Valley High School, there have been incidents of harassment of homosexual students. But it is highly speculative that allowing the plaintiff to wear a T-shirt that says "Be Happy, Not Gay" would have even a slight tendency to provoke such incidents, or for that matter to poison the educational atmosphere. Speculation that it might is, under the ruling precedents, and on the scanty record compiled thus far in the litigation, too thin a reed on which to hang a prohibition of the exercise of a student's free speech.... The school has failed to justify the ban of that [slogan], though the fuller record that will be compiled in the further proceedings in the case may cast the issue in a different light.
Judge Rovner concurred in the judgment, but argued for a much more speech-protective reading of Tinker and Morse than the majority adopted.
My tentative thoughts on the subject:
1. Though the decision is something of a victory for the student speaker, the panel majority opinion would authorize a great deal of speech restrictions. It's a narrow reading of Tinker rights, and a broad reading of Morse's limit on those rights.
2. I'm not troubled by this decision the way I was about the Ninth Circuit's decision on a similar question in Harper v. Poway Unified School Dist.. The Ninth Circuit panel created an expressly viewpoint-based exception to student free speech rights, based on a supposed "right" of "minority" students to be free from "derogatory and injurious remarks directed at [their] minority status such as race, religion, and sexual orientation." The Seventh Circuit expressly rejected this, holding that "people do not have a legal right to prevent criticism of their beliefs or for that matter their way of life." Instead, the Seventh Circuit focused on more traditionally recognized, and facially viewpoint-neutral, concerns about the disruption of the educational process.
3. I also think the concern about disruption of the educational process is quite serious. The public school authorities' job is to educate students, and it's harder to educate students who are distracted, upset, unhappy to be at school, even when they're not actually fighting or dropping out.
4. At the same time, the distinctions the majority opinion draws, and the disagreement between it and the concurrence about how to interpret Tinker and Morse, suggest that the existing doctrine — focused though it is on protecting free speech so long as it doesn't tend to be disruptive — doesn't do a great job of either protecting free speech or preventing disruption. Though the majority's rhetoric seems to nod in the direction of viewpoint neutrality, and though the majority's test is itself facially viewpoint-neutral (in a way the Harper majority's wasn't), the majority would tolerate a wide range of broad, vague, and viewpoint-based restrictions on student speech. At the same time, its approach calls for a case-by-case and hard to predict evaluation of just when speech is likely to be disruptive, an approach that is likely to constrain schools from barring some speech that genuinely is disruptive.
Maybe I'm asking for too much clarity or predictability in what is necessarily going to be a mushy endeavor. But I do think this area of free speech law is especially unclear and unpredictable.
5. Finally, I can just see Justice Thomas, his spiritual sometimes-brother Justice Hugo Black, and, of all people, Stanley Fish, saying "I told you so." Here the Seventh and the Ninth Circuits take very different views of very similar questions; the judges on the Seventh Circuit panel, both purporting to apply the Tinker and Morse tests — or perhaps non-tests? — taking very different view of the same question; and the judges in the majority tentatively allowing some anti-gay speech but not other anti-gay speech without much of a clear explanation of just where the line between the "tepidly negative" and, I suppose, "hotly negative" is drawn. Maybe, they'd say, the best bet is to leave speech in government-run K-12 schools almost entirely to school authorities, rather than muddling through this way. I'm not sure Thomas, Black, and Fish are right on this, but I'm not sure they're wrong, either.