A few weeks ago 34 demonstrators were convicted of violating a law that prohibits holding demonstrations on the grounds of the U.S. Supreme Court. The question this obliviously raises is doesn't such a law violate the First Amendment right to free speech? The answer is probably not. Our discussion in class concerning freedom of speech has dealt mostly with something called "traditional public forums". These generally include streets, sidewalks and public parks. People have an almost unlimited right to engage in speech in this type of forum. But the courts have uniformly held that not all government property can be considered a traditional public forum. In fact, most government property is not considered a public forum and thus speech on this property can be regulated far easier.
Why make a distinction between a traditional public forum and other government property? Generally because the Courts have been sympathetic to the government's position that allowing speech on all government property in any manner would interfere with workings of the government. Imagine if the government had to allow protesters onto military bases or into prisons. Clearly, this kind of expressive activity would interfere with the ability of government to carry out it's mission, whatever that mission might be on the property in question. For purposes of this class, students don't need to know this distinction, but I hope it helps explain why these protesters, who entered the grounds of the Supreme Court, were arrested.