An act that is considered legally impossible to commit is traditionally considered a valid defense for a person who was being prosecuted for a criminal attempt. An attempt is considered to be a
legal impossibility when the defendant has completed all of his intended acts, but his acts fail to fulfil all the required in
elements in a
common law or statutory crime. The underlying rationale is that attempting to do what is not a crime is not attempting to commit a crime. One example of legal impossibility is a person who, thinking that Country 1 has banned the importation of lace from Country 2, attempts to smuggle some "banned" lace into Country 1. The actor believed that their act was a crime, and even fully intended to commit a crime. However, Country 1 does not, in fact, ban lace from Country 2. The traditional approach to understanding the legal impossibility defense is that the mistake (about the content of the law of Country 1) insulates the actor from a conviction for the crime of attempted smuggling. The
legal impossibility may be thought of as reflecting that the actor had not satisfied the
actus reus of the crime (because they had not actually brought a banned substance into the country). To put it another way, merely trying to commit a crime is insufficient to constitute a criminal attempt; for criminal liability to attach, the actor must be attempting to engage in behaviour that is actually criminal.
Legal impossibility can be distinguished from
factual impossibility, which is not generally a defense at common law.
Factual impossibility involves an error as to factual reality (the state of the world) that causes the actor to fail to commit a criminal offence when, if the circumstances were as the actor believed, the offence would have been committed.
Legal impossibility involves an error as to a legal reality (the state of the law). However, it is not always easy to identify whether an actor made a
legal or a
factual mistake. In
State v. Guffey (1953), the defendant shot a stuffed deer, thinking it was alive, and was convicted for attempt to kill a protected animal out of season. In a highly debated reversal, an appellate judge threw out the conviction on the basis of legal impossibility, concluding that it is not a crime to shoot a stuffed deer out of season. ==See also==