In the case of Princeton University v. Schmid (1981), the U.S Supreme Court upheld a New Jersey Supreme Court ruling that private universities could not completely bar non-students from distributing political literature on campus. The case began when Allan Schmid, a non-student, was arrested for trespassing after he distributed political materials at Princeton University without permission. He challenged his arrest, arguing it violated his First Amendment rights to free speech and assembly. While the court acknowledged that private institutions like Princeton have a right to regulate conduct on their property, they also recognized these institutions serve as quasi-public entities due to their educational purpose and public funding received indirectly through tax exemptions or directly in form of grants etc., thus must respect certain constitutional rights such as freedom of speech and assembly within reasonable limits.

In the dissenting opinion for Princeton University v. Schmid, Justice Brennan argued that private universities should not have the right to restrict free speech on their campuses, even if they are privately owned. He believed that when a university opens its campus to the public and allows outside organizations to use its facilities, it becomes a public forum where First Amendment rights should be protected. In this case, he disagreed with the majority's decision which upheld Princeton University's right to limit political solicitation on its property by an outsider who was distributing political literature without permission from university authorities. According to Justice Brennan, such restrictions were unconstitutional as they violated freedom of speech and expression guaranteed under the U.S Constitution.