But the court could rule for Frederick if it determines that he was, as he has contended, conducting a free-speech experiment using a nonsensical message that contained no pitch for drug use.
"It sounds like just a kid's provocative statement to me," Justice David Souter said.
Students in public schools don't have the same rights as adults, but neither do they leave their constitutional protections at the schoolhouse gate, as the court said in a landmark speech-rights ruling from the Vietnam War era.
Morse, now a Juneau schools' administrator, was at the court yesterday. Frederick, teaching and studying in China, was not.
Former independent counsel Kenneth Starr, whose Kirkland and Ellis law firm is representing Morse for free, argued that the justices should defer to the judgment of the principal. Morse reasonably interpreted the banner as a pro-drug message, despite what Frederick intended, Starr said.
School officials are perfectly within their rights to curtail student speech that advocates drug use, he said. "The message here is, in fact, critical," Starr said.
Starr, joined by the Bush administration, also asked the court to adopt a broad rule that could essentially give public schools the right to clamp down on any speech with which they disagree. That argument did not appear to have widespread support among the justices.
Douglas Mertz of Juneau, Frederick's lawyer, struggled to keep the focus away from drugs. "This is a case about free speech. It is not a case about drugs," Mertz said.
Conservative groups that often are allied with the administration are backing Frederick out of concern that a ruling for Morse would let schools clamp down on religious expression, including speech that might oppose homosexuality or abortion. The outcome also could stray from the conservative-liberal split that often characterizes controversial cases.
Justice Samuel Alito, who wrote several opinions in favor of student speech rights while a federal appeals court judge, seemed more concerned by the administration's broad argument in favor of schools than did his fellow conservatives.