ABSTRACT
Modern free speech doctrine creates a rigid two-track system, with one track leading almost invariably to invalidation and the other nearly as certainly to validation. At some basic level free speech doctrine must distinguish between activity eligible for First Amendment protection and that which is not. Free speech case law divides the universe of human activity into four categories: protected speech, unprotected speech, expressive conduct, and nonexpressive conduct. The key question in most of the free speech decisions since the 1970s has been whether the regulation is content based or content neutral. A broad statement about content discrimination that is almost always true, however, is that only content-based restrictions are likely to be invalidated; content-neutral laws, in contrast, are almost always upheld. One important and clearly articulated limit on the rule against content discrimination is the Court's "public forum" jurisprudence.
