In the case of Papachristou et al. v. City of Jacksonville, 1971, the U.S Supreme Court ruled that a city ordinance in Jacksonville, Florida was unconstitutionally vague and violated due process rights under the Fourteenth Amendment. The ordinance criminalized activities such as "wandering or strolling around from place to place without any lawful purpose or object," which were deemed too broad and ambiguous by the court. This decision came after eight individuals were arrested and convicted for violating this law; their convictions were subsequently overturned by this ruling. The court's decision emphasized that laws must be clear enough so ordinary people can understand what conduct is prohibited.

In the case of Papachristou et al. v. City of Jacksonville, there was no dissenting opinion recorded as the Supreme Court's decision was unanimous in favor of Papachristou and his co-petitioners. The court ruled that a Florida vagrancy law under which they were convicted was unconstitutionally vague, violating due process clause because it did not give adequate notice to citizens about what conduct is prohibited and encouraged arbitrary enforcement by police officers.