Also known as: mistake of law · mistake of laws · ignorance of law · ignorantia juris
Written by attorneys · grounded in primary & secondary sources — see below
2 senses
A belief based on a mistake of law does not relieve an actor of liability for trespass to chattels or conversion. The mistake must not have been induced by the other party. Liability turns on the intentional exercise of dominion inconsistent with the owner's rights rather than on the actor's understanding of legal authority.
A belief based on a mistake of law does not relieve an actor of liability for trespass to chattels or conversion. The mistake must not have been induced by the other party. Liability turns on the intentional exercise of dominion inconsistent with the owner's rights rather than on the actor's understanding of legal authority.
Select any source to read its text and confirm it supports the definition.
A mistake of law can serve as a defense when it negates the mental state required for the offense or when the statute was not published or reasonably made available. The defense also applies when the actor reasonably relied on an official statement from a public officer or body charged with interpreting the law.
Select any source to read its text and confirm it supports the definition.
A mistake of law can serve as a defense when it negates the mental state required for the offense or when the statute was not published or reasonably made available. The defense also applies when the actor reasonably relied on an official statement from a public officer or body charged with interpreting the law.
Each sense below has its own examples, sources, and questions.
Maurice Marshall checked out of a hotel owned by Harborview Hotels but left his violins behind. Manager Ortiz believed a state innkeeper statute authorized disposal after thirty days and donated the instruments to charity. Marshall sues for conversion. Ortiz's mistaken belief about legal authority provides no defense because the mistake was not induced by Marshall and the donation constituted unauthorized dominion over the chattels.
No. A mistaken belief that a statute or policy authorizes disposal of property does not relieve liability when the mistake is not induced by the owner. The actor remains liable once intentional dominion inconsistent with the owner's rights is shown.
Supporting sources
Miguel Mendoza drove the getaway car during a robbery in which his accomplices killed the victims. Mendoza believed his limited role would not expose him to the death penalty under state felony-murder rules. After conviction and sentencing, he seeks habeas relief. The court examines whether his mistaken understanding of the law regarding accomplice liability negates the required mental state for capital punishment.
Mariam Mansour's home was searched pursuant to a warrant that misdescribed the items to be seized. The officers believed the warrant was valid under Fourth Amendment standards despite the error. Mansour moves to suppress the evidence. The court considers whether the officers' mistaken interpretation of the warrant's legal sufficiency supports qualified immunity or renders the search unreasonable.
Mohan Malhotra failed to file tax returns after concluding that wages are not taxable income under the Internal Revenue Code. He held this belief in good faith but without objective reasonableness. Charged with willful failure to file, Malhotra asserts his mistake of law as a defense. The court evaluates whether his subjective misunderstanding negates the statutory willfulness element.
Mason McCarthy possessed an unregistered machine gun after concluding that the National Firearms Act did not apply to weapons he inherited from a relative. He had no actual knowledge of the registration duty. Prosecuted for knowing possession of an unregistered firearm, McCarthy claims his mistake of law defeats the mens rea element. The court assesses whether the statute requires proof that the defendant knew of the legal duty to register.
Melanie Morris carried a firearm while believing her position as a federal corrections officer qualified her as a peace officer exempt from state licensing requirements. Charged with unlawful possession, she asserts a mistake-of-law defense. The court determines whether her erroneous interpretation of the exemption statute negates the knowledge element or whether the defense is unavailable under the state's strict approach to mistakes of law.
A mistake of law is a defense if it negates the required mental state or if the statute was not published or reasonably made available. The defense also applies when the actor reasonably relied on an official statement from the public officer or body charged with interpreting the law.
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Yes when the rule was circulated only through a confidential listserv inaccessible to the defendant and was exempted from ordinary publication. The defense succeeds if the government failed to make the law reasonably available to actors in the defendant's position.
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No. Reliance on a statement from a private entity does not qualify as reasonable reliance on an official statement from a public officer or body. The defense under the Model Penal Code therefore does not apply.
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…188, 191-193 (CA1 1985), we granted certiorari, 493 U. S. 1068 (1990). II The general rule that ignorance of the law or a mistake of law is no defense to criminal prosecution is deeply rooted in the American legal system. See, e. g. , United States v. Smith , 5 Wheat. 153, 182 (1820) (Livingston, J., dissenting); Barlow…