Chief Justice Roberts, writing for the majority, concluded that the school officials did not violate the First Amendment. To do so, he made three legal determinations: first, that "school speech" doctrine should apply because Frederick's speech occurred "at a school event"; second, that the speech was "reasonably viewed as promoting illegal drug use"; and third, that a principal may legally restrict that speech—based on the three existing First Amendment school speech precedents, other Constitutional jurisprudence relating to schools and a school's "important, indeed, perhaps compelling interest" in deterring drug use by students.