18 Pa.C.S. § 5502: Failure of disorderly persons to disperse upon official order.

Where three or more persons are participating in a course of disorderly conduct which causes or may reasonably be expected to cause substantial harm or serious inconvenience, annoyance or alarm, a peace officer or other public servant engaged in executing or enforcing the law may order the participants and others in the immediate vicinity to disperse. A person who refuses or knowingly fails to obey such an order commits a misdemeanor of the second degree.