Chicago v. Morales


A criminal law is unconstitutionally vague if an ordinary person could not understand what conduct is criminalized, and if the vagueness of the law encourages arbitrary and potentially discriminatory enforcement.


The city of Chicago passed an ordinance that prohibited individuals from loitering in public places. This was based on findings by a city commission that supported the conclusion that violent crimes were increasing because of street activity by gangs, which established control over areas while they were loitering. The commission also found that loitering by gang members in public intimidated ordinary residents of the city and restricted access to certain areas. The Gang Congregation Ordinance thus forbade suspected street gang members to loiter in public places, an offense that could be punished by a fine of up to $500, imprisonment, and community service.

The ordinance contained four main elements. A police officer must reasonably believe that two or more people in a certain pace are gang members, they must be loitering at that place without any apparent purpose, the officer must order them to disperse, and they must disobey that order. Morales and several associates were charged with violating the ordinance. They argued that it was unconstitutionally vague because it covered a broad range of activity beyond the loitering that allegedly was harmful. The state supreme court agreed, ruling that police officers had unlimited discretion to define the nature of the loitering, and the Constitution required specific limits on that discretion.