9.54.010 Riot.
A. A person is guilty of riot if:
1. Simultaneously with two or more other persons he engages in tumultuous or violent conduct and thereby knowingly or recklessly creates a substantial risk of causing public alarm; or
2. He assembles with two or more other persons with the purpose of engaging, soon thereafter, in tumultuous or violent conduct, knowing that two or more other persons in the assembly have the same purpose; or
3. He assembles with two or more other persons with the purpose of committing an offense against a person or property of another who he supposes to be guilty of a violation of law, believing that two or more in the assembly have the same purpose.
B. Any person who refuses to comply with a lawful order to withdraw given to him immediately prior to, during, or immediately following a violation of subsection A of this section is guilty of riot. It is no defense to a prosecution under this subsection that withdrawal must take place over private property; provided, however, that no persons so withdrawing shall incur criminal or civil liability by virtue of acts reasonably necessary to accomplish the withdrawal.
C. Riot is a class B misdemeanor. (Code 1975 § 13-911)