Section 144

Unlawful assembly is a legal term to describe a group of people with the mutual intent of deliberate disturbance of the peace. If the group are about to start the act of disturbance, it is termed a rout; if the disturbance is commenced, it is then termed a riot. In Britain, the offence was abolished in 1986.

By the 19th century, unlawful assembly was the term used in English law for an assembly of three or more persons with intent to commit a crime by force, or to carry out a common purpose (whether lawful or unlawful), in such a manner or in such circumstances as would in the opinion of firm and rational men endanger the public peace or create fear of immediate danger to the tranquillity of the neighbourhood. In the Year Book of the third year of Henry VII's reign assemblies were referred to as not punishable unless in terrorem populi domini regis. It was suggested that legislation first became necessary at a time when it was usual for those landed proprietors who were on bad terms with one another to go to market at the head of bands of armed retainers. An assembly, otherwise lawful, was not made unlawful if those who take part in it know beforehand that there will probably be organized opposition to it, and that it may cause a breach of the peace. All persons may, and must if called upon to do so, assist in dispersing an unlawful assembly. An assembly which was lawful could not be rendered unlawful by proclamation unless the proclamation was one authorized by statute. Meetings for training or drilling, or military movements, were unlawful assemblies unless held under lawful authority from the Crown, the Lord Lieutenant, or two justices of the peace.

An unlawful assembly which has made a motion towards its common purpose was termed a rout, and if the unlawful assembly should proceed to carry out its purpose, e.g. begin to demolish a particular enclosure, it became a riot. All three offences were misdemeanours in English law, punishable by fine and imprisonment. The offence was abolished by the Public Order Act 1986.

The common law as to unlawful assembly extended to Ireland, subject to special legislation. The law of Scotland included unlawful assembly under the same head as rioting.

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