Written by attorneys · grounded in primary & secondary sources — see below
A defense to attempt under which a defendant cannot be convicted if the acts she intended to perform, even if completed exactly as planned under the circumstances she believed to exist, would not constitute a crime. The defense applies when an essential element of the target offense would be absent even under the defendant's believed facts.
Sources & Authorities
How it applies
Common Examples
5
Bar Grievance Affidavit Scheme
Lola Langley directed her paralegal to obtain a sworn statement from a former client falsely claiming a rival firm missed a filing deadline. She planned to submit the affidavit to bar counsel even though official guidelines categorically excluded client affidavits on timing issues and required reliance solely on court records. Because the statement could never satisfy the materiality element of subornation of perjury under the facts as Lola believed them, she cannot be convicted of attempted subornation of perjury.
Rating Firm Net Worth Statement
Logan Lane urged a former client to sign a sworn statement falsely inflating the client's net worth for submission to a private rating firm. Logan believed the firm reviewed individual investor data and would downgrade a competitor as a result. Because the firm's actual policies made any such statement incapable of affecting rankings, the planned conduct would not have satisfied the materiality element of subornation of perjury even if completed exactly as intended.
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Cases
Common Law
Casebooks
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Course Outlines
Study Supplements
Dictionaries
Basketball Point Spread Agreement
Latoya Lane and a professional gambler agreed that Latoya would miss free throws to affect the point spread in an upcoming game. Both believed Latoya would play, yet league rules had already placed her on the inactive list and barred her from entering the arena. Because the agreement targeted conduct that could never occur under governing league bylaws, Latoya cannot be convicted of attempted game-fixing.
Three Strikes Sentencing Challenge
Levi Lowe attempted to commit a minor theft while believing his prior convictions qualified as strikes under a recidivist statute. He planned every act under the mistaken belief that the statute would apply. Because the believed facts would not have triggered the enhanced penalty even if the current offense had been completed exactly as intended, the legal impossibility defense bars conviction for attempted sentence enhancement.
Marriage License Restriction
Lila Lin attempted to obtain a marriage license while subject to an outstanding child support order that state law treated as an absolute bar. She planned every act under the belief that the restriction would apply. Because the believed facts would render issuance of the license legally impossible under the statute even if the application were completed exactly as intended, the defense precludes attempt liability.
Common questions
Frequently Asked
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How does legal impossibility differ from factual impossibility?+
Legal impossibility is a defense because the intended conduct would not be criminal even if completed exactly as planned. Factual impossibility is not a defense because the conduct would be criminal if the unknown facts had been as the defendant believed them to be.
Supporting sources
Does legal impossibility apply to conspiracy charges?+
Yes. If the parties agree to commit an act they believe is criminal but that is not actually prohibited by law, they cannot be convicted of conspiracy because the object of the agreement is not unlawful.
Supporting sources
Is legal impossibility a defense to solicitation?+
Yes. A person does not commit solicitation by encouraging conduct that is not a crime, even if the solicitor believes the conduct is illegal.
Supporting sources
What is the test for determining whether legal impossibility applies?+
The court asks whether the defendant, having completed every intended act under the circumstances she believed to exist, would have committed a crime. If an essential element such as materiality would be missing, the defense bars conviction.
Supporting sources
Does the Model Penal Code recognize legal impossibility as a defense?+
No. The Model Penal Code provides that factual or legal impossibility is not a defense if the crime could have been committed had the attendant circumstances been as the actor believed them to be.
Supporting sources
434 U.S. 374 (1978)Constitutional Law
…considered in Jobst as to warrant a different result. In the case of some applicants, this statute makes the proposed marriage legally impossible for financial reasons; in a similar number of extreme cases, the Social Security Act makes the proposed marriage practically impossible for the same reasons. I cannot conclude that such a…