[Latin: a guilty act]
The prohibited conduct or behaviour that the law seeks to prevent. Although commonly referred to as the “guilty act” this is rather simplistic, as the actus reus includes all the aspects of the crime except the accused's mental state (see mens rea). In most cases the actus reus will simply be an act (e.g. appropriation of property is the act of theft) accompanied by specified circumstances (e.g. that the property belongs to another). Sometimes, however, the actus reus may be an omission to act (e.g. failure to prevent death may be the actus reus of manslaughter: R v Stone and Dobinson  QB 354) or it may include a specified consequence (death resulting being the consequence required for the actus reus of murder or manslaughter). In certain cases the actus reus may simply be a state of affairs rather than an act (Winzar v Chief Constable of Kent (1983) The Times 28 March 1983).