Also known as: impossible attempt · impossibility of attempt · factual impossibility · legal impossibility
Written by attorneys · grounded in primary & secondary sources — see below
A doctrine in criminal law that distinguishes factual impossibility, which supplies no defense to attempt, solicitation, or conspiracy, from legal impossibility, which bars liability when the defendant's intended acts would not constitute a crime even if completed exactly as planned.
Iain Irons and Idina Iverson agreed to rob a bank they believed held substantial cash reserves. Unknown to them, the bank had closed permanently the week before. Iain and Idina are charged with conspiracy. The agreement and shared intent establish guilt even though the robbery could never occur.
Imran Iyer submitted a sworn statement he believed contained a material falsehood in order to obstruct justice. The statement was in fact immaterial under the governing statute. Even if every act unfolded exactly as Imran intended, no perjury would have occurred, so he cannot be convicted of attempt.
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Imani Idowu offered Ivy Ibarra cash to vandalize a house Imani believed still stood. The house had already burned down in an unrelated fire. Imani is guilty of solicitation because her culpability is measured by the facts as she believed them to be.
Isabella Ingram placed what she believed was a working explosive on a plane to kill the passengers. The detonator lacked a critical part and could never explode. Isabella is liable for attempted murder because the factual impossibility does not excuse her substantial step taken with intent to kill.
Stagehand Tim cut the cable he believed supported a spotlight above performer Greg. Unknown redundant lines prevented any fall. Tim is guilty of attempted battery because the unknown factual condition supplies no defense under the common law rule.
Promoter Dean urged crew member Charles to assault critic Marshall at a festival Dean believed Marshall still attended. Marshall had already left hours earlier. Dean remains guilty of solicitation because factual impossibility does not bar liability when measured by the circumstances as Dean believed them.
No. Common law measures culpability by the facts as the defendant believed them to be. If those believed facts would have made the completed conduct criminal, the defendant is guilty of attempt even though an unknown physical condition prevented success.
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Legal impossibility exists when the intended acts would not constitute a crime even if completed exactly as planned. Factual impossibility arises from an unknown physical condition that prevents success. Only legal impossibility supplies a defense to attempt.
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No. The solicitor's guilt is judged by the circumstances as the solicitor believed them to be. The offense is complete upon the request made with specific intent that the crime occur, regardless of whether the solicited act could actually be performed.
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The rule punishes the dangerous combination of culpable intent and substantial steps toward crime. It prevents defendants from escaping liability solely because unknown external facts thwarted completion, thereby deterring conduct that would have been criminal under the believed circumstances.
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…of whether the result can be accomplished. And even if the result, which would be death in this case, was a scientific or factual impossibility. In this case if you should be convinced beyond a reasonable doubt by the State's evidence that Mr. Smith's purpose was to kill Sheriff's Officer Waddington by biting him it does not matter…