The minimum requirement for criminal liability is the performance by a person of conduct which includes a voluntary act or the omission to perform an act which he is physically capable of performing. If that conduct is all that is required for commission of a particular offense, or if an offense or some material element thereof does not require a culpable mental state on the part of the actor, the offense is one of strict liability. If a culpable mental state on the part of the actor is required with respect to any material element of an offense, the offense is one of mental culpability. (Ord. 200 §1, 1982)