The criminal offense of unlawful assembly generally means the assembly of multiple persons resulting in conduct that (1) is intended to commit a breach of the peace or other unlawful act; (2) creates an immediate danger of damage to property or injury to persons; (3) substantially obstructs law enforcement or other governmental functions or services; (4) is tumultuous or violent and likely to cause public alarm; or (5) deprives any person of a legal right or disturbs any person in the enjoyment of a legal right by using force or the threat of force.

Unlawful assembly laws vary from state to state and some states have related offenses such as rioting, riots and routs, participating in a riot, inciting a riot, failing to disperse, and disturbing the peace. The criminal offense of unlawful assembly may be included in the definition of one or more of these offenses or may be a separate criminal offense. These laws are generally located in a state’s statutes—often in the penal or criminal code.

In New York, the criminal offense of unlawful assembly is defined under New York Penal Law Section 240.10. An unlawful assembly occurs when five or more persons assemble with the intent to engage in conduct constituting a riot or with the purpose to commit any other criminal act. The law requires that the assembly must have the potential to create a clear and present danger of causing a breach of the peace or significant harm to persons or property. This offense is considered a class B misdemeanor in New York. Additionally, related offenses such as rioting (Penal Law Sections 240.05 to 240.08) and disorderly conduct (Penal Law Section 240.20) are also defined in the New York Penal Code. These laws are designed to maintain public order and safety by prohibiting group conduct that threatens to disturb the peace or endanger the community.