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Kilbride was charged under the Traffic Regulations Act for operating a motor vehicle without a current “warrant of fitness” (registration) displayed. He did in fact have one, and it was displayed, however it was somehow removed when he left the car – which was also the time that the officer gave him the ticket for the offence. He subsequently proved that the car was registered and that the warrant had been displayed when he left the car. However, the offence simply states that you must display the warrant at all times, and when the officer gave the ticket the warrant was not displayed. He was convicted at trial, which he appealed.


  1. Can something done perfectly innocently by a defendant become an offence by reason of an intervening cause beyond his control, and which produced an effect outside of his knowledge?


Appeal allowed, conviction quashed. ???


Woodhouse holds that this is not a mens rea issue. He quotes Halsbury's, which states, "a person cannot be convicted of any crime unless he has committed an act prohibited by law, or failed to live up to a legal duty. The act or omission must be voluntary". Therefore, the defendant must be shown to be responsible for the physical ingredient of the crime to be convicted. Until this is proven, the question of mens rea is irrelevant. The actus reus must be committed voluntarily, and it is not the line of conduct that produces the prohibited event, but the event itself. Here, the prohibited event is permitting a vehicle to be on the road accompanied by an omission to display a warrant. Both must occur simultaneously; however, in this case only the first aspect was present. It was the extraneous cause that resulted in the conditions for conviction becoming present, and the defendant did not voluntarily bring this about. Therefore, as the actus reus is not proven, the mens rea issue does not matter.


  • Disregarding any mental elements of an offence, a person cannot be criminally responsible for an act or omission unless it was done or omitted in circumstances where there was some other course open to him.
  • If the actus reus of the offence is committed involuntarily, then the defendant cannot be convicted.