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 Hampshire, the criminal offense of unlawful assembly is addressed under RSA 644:2, which defines 'Riot' and 'Unlawful Assembly.' According to this statute, an unlawful assembly occurs when three or more persons assemble with a common purpose to engage in conduct that would constitute a breach of the peace, or the assembly results in conduct that creates a clear and present danger of damage to property or injury to persons. The law also covers situations where the assembly substantially obstructs law enforcement or other governmental functions, or is violent or tumultuous, likely to cause public alarm. New Hampshire law distinguishes between 'riot,' which requires an overt act in furtherance of the assembly's purpose, and 'unlawful assembly,' which does not require such an act. Penalties for participating in an unlawful assembly can range from a misdemeanor to a felony, depending on the circumstances and the presence of any aggravating factors. It's important for individuals to understand that engaging in protest or assembly is legal when done peacefully and without the intent to commit a crime or incite violence. An attorney can provide specific guidance on the nuances of these laws and how they might apply in a given situation.