Is Reasonableness Required?

Is Reasonableness Required?

Courts often say that a mistake excuses only if it was reasonable, and the statement sounds like a natural companion to the negation test taught above. It is an uncritical generalization. Section 2.04(1)(a) makes a mistake a defense when it negatives the purpose, knowledge, belief, recklessness, or negligence that the offense requires for a material element, and nothing in that test makes reasonableness a separate condition.¹ Whether the quality of the defendant's thinking matters therefore depends on which mental state the offense attaches to the element the mistake touches.² The reasonableness question is a mens rea question in another form.

The generalization persists for two reasons. Some decisions assert, usually without explanation, that the error must be reasonable, and imprecise drafting sometimes leaves unclear what mental state the offense requires in the first place.³ United States v. Short shows the first reason at work. The defendant there was convicted of assault with intent to commit rape and asked for an instruction that he could not be convicted if he believed the woman had consented. The conviction was affirmed because the instruction failed to say that the belief had to be reasonable, and the court reasoned from the rule that governs rape itself.⁴ The dissent answered that the offense charged required a purpose of rape, and that such a purpose cannot exist in someone who believes, even unreasonably, that the woman is consenting.⁵ The majority had taken a reasonableness rule from a different offense without first asking what the offense on trial required.

The dissent has the better of the argument, and the reason is mechanical. Reasonableness is the yardstick of negligence, since it asks what a prudent person would have perceived. If it is read into every mistake claim as a general condition, every offense that demands purpose, knowledge, or belief quietly becomes a negligence offense, and a defendant who lacked the culpable mind is convicted for a carelessness the legislature never made criminal. A reasonableness inquiry belongs where the offense itself names negligence, or where a factfinder must decide whether a claimed belief was honestly held. The three parts below take those pieces in turn, beginning with the mental states for which an honest mistake is enough.

Purpose, Knowledge, and Belief

Where an offense requires purpose, knowledge, or belief about an element, an honest mistake negates that element even when the mistake was careless or unreasonable. The reason lies in what those mental states demand. For crimes committed purposely or knowingly, and for recklessness as well, the defendant must know that the attendant fact exists or that there is a substantial probability that it exists, so a defendant who honestly believes the fact does not exist lacks that awareness no matter how poorly the belief was formed.⁶ An offense that makes belief itself the required mental state asks even more directly what the defendant actually believed. In each case the quality of the reasoning behind the belief has no bearing on whether the awareness is present, which is why a reasonableness gloss has nothing to attach to.

The Code's drafters regarded this as a point that holds even without a provision on the subject, because a crime requiring intention cannot be committed by someone whose mistake negates the intention.⁷ They found no justification for requiring a mistake to be reasonable when the element calls for purpose or knowledge, and they treated general statements to the contrary as products of loose generalization about general and specific intent.⁸ The Short dissent applied the same reasoning to a second offense: on a charge of knowingly possessing marijuana, even a negligent failure to recognize what the cigarettes were would be a defense, because knowledge is a higher and different requirement than negligence.⁹

The two visitors differ in a single respect, which is whether the claimed belief was genuinely held, and neither outcome turns on whether a prudent owner would have shared it. Willful blindness does not reintroduce reasonableness, because the Code treats a defendant who sees a high probability of a fact as knowing it.¹⁰ The trap on an exam is to carry the phrase honest and reasonable mistake into an offense that requires purpose, knowledge, or belief; for those mental states the analysis stops at honesty.

When Reasonableness Matters

A reasonableness requirement has a genuine place in two situations, and the logic of the Code explains each. The first is the offense whose mental element for the circumstance is negligence, which § 2.04(1)(a) names among the mental states that a mistake can negate.¹² Negligence is measured against a reasonable person, so a mistake negates it only when a reasonable person could have made the mistake, and under the Code a mistake that is a gross deviation from what a reasonable person would understand leaves liability in place.¹³ The reason is that a legislature that punishes negligence has chosen to treat carelessness in perceiving the circumstance as the culpable conduct, so the quality of the defendant's belief is the very thing the offense measures. The gross-deviation standard also keeps the requirement demanding, since criminal negligence calls for more than the ordinary carelessness that would support tort liability.¹⁴

The second place reasonableness appears is evidentiary and does not depend on how the offense is defined. Even when the mental state is purpose, knowledge, or belief, the factfinder must decide whether the defendant actually held the claimed belief, and a mental state can only be inferred from surrounding circumstances. A story that no sensible person would credit invites the inference that the defendant did not really believe it, so unreasonableness is circumstantial evidence on the question of sincerity. That use adds no element to the offense, because a jury that finds the belief was in fact held, however foolish, must find the mental state unproved.¹⁵ Treating the same circumstances as a rule that the belief must be reasonable would convert an evidentiary hint into a negligence requirement the statute never wrote.

Where the law itself writes reasonableness into an offense or a defense, the requirement comes from that text, and the statutory defenses taken up later in this chapter are the place to look for it.

Common-Law Labels and the Code

Decisions that predate or ignore the Code usually frame the question in a different vocabulary, and that vocabulary has to be translated before it can be compared with § 2.04(1)(a). The common-law approach ties the sufficiency of an honest mistake to the distinction between specific-intent and general-intent crimes, and it adds a second distinction between mistakes of fact and mistakes of law. The Code disregards the specific-intent and general-intent classification and looks to the function the mistake performs.¹⁸ The history explains how the labels came to carry a reasonableness gloss. Before the nineteenth century an honest mistake exculpated whether or not it was reasonable. Courts then adopted the emerging reasonable-person standard, so that only reasonable mistakes acquitted, except for specific-intent crimes, where the legislature was taken to have meant that only the genuinely bad should be convicted and an honest mistake therefore sufficed.¹⁹ The common-law result was all or nothing: a reasonable mistake exculpated, while an honest but unreasonable one left the defendant punished as though no mistake had been made.²⁰

The labels mislead because they do not say what mental state an element carries. The Short dissent shows the translation. Assault with intent to rape is a specific-intent crime because its definition demands a purpose, and a purpose cannot coexist with an honest belief in consent, while the rape rule the majority borrowed rests on an offense understood not to include knowledge of the woman's lack of consent.²¹ A reasonableness requirement attached to the general-intent offense therefore did the work of a negligence standard on an element for which the statute named no mental state. The Code's commentary criticizes exactly this kind of generalization about general and specific intent, because it obscures the simple point that the mental state the offense names controls the answer.²² Where imprecise drafting leaves the mental state unstated, the Code supplies purpose, knowledge, or recklessness as the required mental state for each material element.²³

On an exam, the first step is to determine which regime governs. In a common-law jurisdiction the label predicts the answer: an honest mistake suffices for a specific-intent crime, and honesty plus reasonableness is required for a general-intent crime. In a Code jurisdiction the label drops out, and the analysis runs through the mental state attached to the element, with honesty alone enough for purpose, knowledge, and belief, and reasonableness required for negligence. Deciding the question by the label alone risks importing a negligence standard that the offense never contained.

Purpose, Knowledge, and Belief

When the mental state attached to an element is purpose, knowledge, or belief, the only question about the defendant's mistake is whether it was honestly held. Each of these states is defined by what the defendant personally aimed at or was aware of. The prosecution must therefore prove that aim or awareness in the defendant, and evidence that a prudent person would have shared it does not prove it in this one.²⁵ Knowledge shows the mechanism most plainly. A defendant who acts knowingly must be aware that an attendant fact exists, or that there is a substantial probability that it exists, so a defendant who honestly believes the fact does not exist lacks that awareness, however carelessly the belief was formed.²⁶ An offense that names belief itself as the mental state turns on what the defendant actually believed in the same way, and a purpose to bring about a forbidden result cannot coexist with a sincere conviction that the circumstance making the act forbidden is absent.

People v. Navarro applies this rule to a theft charge. The defendant took building beams that he claimed to believe were worthless and abandoned, and the trial court told the jury that it should convict unless that belief was reasonable, even if he held it in good faith.²⁷ The appellate court reversed. Theft requires a specific intent to steal, and the prosecution must prove that the defendant himself had that intent, which it does not do by showing that a reasonable person in his position would have had it.²⁸ Because there is no such thing as theft by negligence, a genuine belief that the property may be taken negates the intent however much carelessness lay behind the belief.²⁹

The flaw in the instruction is easy to state in terms of mental states. Reasonableness is the yardstick of negligence, so an instruction that convicts a defendant for holding an unreasonable belief punishes carelessness in forming the belief. The legislature that defined theft by an intent to steal never made carelessness of that kind a crime. Section 2.04(1)(a) reaches the same result by a more direct route, because a mistake that negatives the purpose, knowledge, or belief the offense requires is a defense without any further condition of reasonableness.³⁰ The common-law decision speaks the language of specific intent, and a later part of this chapter translates that vocabulary into the Code's terms.

The unreasonableness of a belief still has a job, but the job is evidentiary. The Navarro court acknowledged that a jury which finds the defendant's belief unreasonable may infer that he did not actually hold it in good faith.³¹ If the jury instead concludes that he did honestly hold the belief, however unreasonable it was by the standard of a hypothetical prudent person, he is entitled to acquittal, because the intent the statute requires has not been established.³² Take the same beams and the same claim of abandonment: a jury that disbelieves the claim finds the intent to steal present, while a jury that believes it finds the intent absent. The facts about the beams are identical in both outcomes, and the only variable is whether the jury accepts that the belief was genuine.

A claimed belief is a question of fact for the jury even when the prosecution is the party attacking it. In State v. Smith, an HIV-positive inmate who bit a corrections officer was convicted of attempted murder. He argued that he had known a bite could not transmit the virus, and the jury rejected that claim in light of his repeated threats, over several months, to infect officers by biting or spitting.³³ The appellate court treated the defendant's own belief and intent as the controlling facts, holding it sufficient that he himself believed he could cause death by biting.³⁴ The case is useful here only for that point, since the sincerity of a claimed belief is decided from everything the defendant said and did.

The dissent in United States v. Short supplies two illustrations of the principle that knowledge and purpose sit above negligence. On a charge of knowing possession of marijuana, possession in that sense denotes conscious knowledge of the thing possessed. A defendant who never realized the cigarettes were marijuana therefore has a defense even if a more careful person would have found out, because knowledge is a higher and different requirement than negligence.³⁵ The second illustration is the charge in Short itself, assault with intent to commit rape. That offense names a purpose, namely intercourse against the woman's will, and the purpose cannot exist in a defendant who believes, even unreasonably, that she is consenting.³⁶ The majority affirmed the conviction because the requested instruction omitted a reasonableness qualification borrowed from the law of rape itself.³⁷ The next part returns to that majority position when it asks where a reasonableness requirement does belong.

The second hauler's case marks the outer edge of the rule. The Code treats knowledge of a fact as established when a person is aware of a high probability that it exists, unless he actually believes that it does not exist.³⁸ Honesty remains the test even here, since the exception turns on actual belief, but a story that contradicts what the defendant plainly perceived is poor evidence that the belief was real. On an exam, the error to avoid is asking whether the belief was sensible when the offense calls for purpose, knowledge, or belief. The question is whether the defendant held it, and unreasonableness matters only as evidence on that point.

When Reasonableness Matters

The earlier discussion of purpose, knowledge, and belief showed that an honest mistake negates those mental states however carelessly it was formed. Reasonableness has not left the doctrine, though, and the courts that insist a mistake be reasonable are sometimes correct. The traditional general statement requires that the mistaken belief be honestly held, rest on reasonable grounds, and concern facts that would have made the conduct lawful had they been as supposed, yet the same authority recognizes exceptions running in both directions: an honest mistake without reasonable grounds sometimes exculpates, and a well-grounded belief sometimes fails to save the defendant.⁴⁰ Decisions often announce that the error must be reasonable without saying why, which is a recurring source of confusion.⁴¹ The exceptions follow a pattern, because each corresponds to a different relationship between the mistake and the mental state the offense attaches to the element. Reasonableness belongs in two places: where the element carries negligence, and where the element carries no culpability at all.

The first place is negligence, which the text of § 2.04(1)(a) lists beside purpose, knowledge, belief, and recklessness as a mental state that a mistake may negate.⁴² The listed states differ in what they measure. Purpose, knowledge, belief, and recklessness ask what the defendant was actually aiming at or aware of, so a sincere mistake about the fact removes them, however unreasonable it was.⁴³ Negligence asks what the defendant should have been aware of, and the Code frames the shortfall as a gross deviation from what a reasonable person would have understood.⁴⁴ A mistake therefore negates negligence when it falls short of that deviation, as a mistake a reasonable person might share does. In this setting reasonableness is the content of the mental state itself, so asking whether the mistake was reasonable and asking whether negligence is proved are the same question.

The two shooters held equally sincere beliefs, so honesty cannot be what separates them. The statute asks about negligence, and negligence is measured against what a reasonable person would have perceived from the shooter's position. The first hunter's mistake is one that standard tolerates, and the second hunter's mistake is one it condemns.

Decisions from other fields show how sharply the law separates negligence from the subjective states, and what it looks like when reasonableness is itself the governing standard. In Daniels v. Williams, a constitutional tort case, the Court described a lack of due care as a failure to measure up to the conduct of a reasonable person and treated the difference between negligence and intent as plain.⁴⁵ In New York Times Co. v. Sullivan, a constitutional defamation case, a newspaper's failure to check an advertisement against its own files amounted to no more than negligence and so could not supply the recklessness that the First Amendment standard demands.⁴⁶ In Heien v. North Carolina, a Fourth Amendment case, a police officer's mistake of fact or law was judged by an objective standard that ignored what the particular officer actually understood.⁴⁷ Those settings make reasonableness the standard to be met, whereas the Code asks about it only when the offense attaches negligence to the element.

The second place is the element to which the offense attaches no culpability. Section 2.04(1)(a) operates only on a mental state the offense requires, so where the offense requires none as to the element the defendant misjudged, a mistake has nothing to negate, and even an honest and reasonable belief leaves the element established.⁴⁸ A statute against selling alcohol to a minor shows the structure. Most courts would require the prosecution to prove that the seller knew the product was liquor, so a seller who thought he was pouring water has a defense, but the customer's age is typically the element that carries strict liability.⁴⁹ A bartender who checks a driver's license and a union card that both show the customer to be twenty-four is guilty if the customer is seventeen, however reasonable the reliance, and the result is the same if the bartender demands every conceivable document and the documents themselves turn out to be wrong.⁵⁰

Strict liability on an element places the risk of error about that element on the actor, and the practical reason is easy to see. A rule that excused every sincere mistake would turn the trial into a contest over what the defendant privately believed, which is the very inquiry the offense was read not to require. That explains why courts and legislatures that soften such offenses usually reach for an objective limit, since a limit based on reasonable grounds confines a defense the offense never created to defendants who took care. Authority recognizes that a rule denying any mistake defense to a strict liability offense goes too far, but also that even a well-grounded mistake does not exculpate when greater care, of a kind not unreasonable to require in the situation, would have exposed it.⁵¹ Some jurisdictions fix the standard by statute, and the statutory standards vary.⁵²

People v. Hernandez frames the question for the age of a victim. The defendant there was charged with statutory rape of a girl who was seventeen years and nine months old, and he sought to present evidence that he had in good faith and on reasonable grounds believed her to be eighteen or older.⁵³ What a belief about age can accomplish depends on what the offense requires as to age. If the statute attaches a mental state to age, a mistake can negate it under the usual analysis. If age is an element with no culpability attached, the belief negates nothing, and any relief depends on a defense that a court or legislature chooses to recognize, a setting in which a reasonable-grounds limit is a familiar form.

United States v. Short is the standard example of a court importing reasonableness into an offense that did not call for it. The defendant was convicted of assault with intent to commit rape and asked for an instruction that he could not be convicted if he believed the woman had consented. The court affirmed because the requested instruction did not say the belief had to be reasonable, reasoning that on a rape charge a defendant would be entitled only to an instruction that a reasonable belief in consent is a defense.⁵⁴ That reasoning treated the rape rule as the model, and the rape rule works as a limit because rape, on the reading the majority relied on, does not include an element of knowledge of the woman's lack of consent, so not every mistaken belief in consent negates what that offense requires.⁵⁵ The position belongs to the Short majority, and the Code's approach would instead ask what mental state attaches to consent in the offense charged. As the earlier discussion showed, assault with intent to rape names a purpose, and a purpose cannot coexist with an honest belief in consent. A reasonableness limit that fits an offense with no culpability element on consent therefore does not carry over to an offense that has one.

Reasonableness also appears in a different kind of claim, where the mistaken belief concerns circumstances that would have made the defendant's act lawful. A dissenting opinion in an assault prosecution illustrates it. The defendant had used force against men who, unknown to him, were plain-clothes detectives lawfully apprehending a suspected disorderly person, and the defense rested on a belief that he was lawfully assisting another. The dissent reasoned that criminal intent requires an awareness of wrongdoing, that an honest and reasonable belief in facts which would make the force lawful leaves no such awareness, and that the reasonableness of the belief is a question for the trier of fact.⁵⁶ California's pattern jury instruction on mistake of fact is built the same way, telling jurors that a person is not guilty who acts under an honest and reasonable belief in facts that would make the act lawful.⁵⁷

Reasonableness in these claims attaches to a defense framed around circumstances that would make the act lawful, and no mental state the offense names supplies it, so it comes from the law that defines the defense. Section 2.04(1)(b) provides that a mistake is a defense where the law itself says the state of mind the mistake establishes constitutes one, and the later discussion of statutory defenses takes up that route.⁵⁸ On an exam, the common errors are to carry the phrase honest and reasonable into every mistake problem, or to discard reasonableness altogether after learning that honesty suffices for purpose, knowledge, and belief. Reasonableness depends on the mental state attached to the mistaken element, and the way to find out is to work through the offense element by element.

The second step does the real work, because the same careless misjudgment of a buyer's age acquits under an offense requiring knowledge of age, convicts under one requiring negligence if the misjudgment was a gross deviation, and convicts regardless under one requiring nothing. The facts of the mistake never change across those three offenses. Only the mental state attached to the element changes, and with it the role that reasonableness plays.

Common-Law Labels and the Code

The earlier discussion reached its results by asking what mental state the offense attaches to the mistaken element. Courts and examiners who work from the common law reach many of the same results by a different route, and its vocabulary fills both cases and exam questions. That route sorts offenses into specific-intent and general-intent crimes, and it separately sorts mistakes into mistakes of fact and mistakes of law. The Model Penal Code observes neither sorting. Its treatment of mistake turns on the function the mistake performs, meaning whether it negates a mental state the offense requires.⁶⁴ Moving between the two vocabularies is therefore a matter of translation, and the Code's inquiry remains the one under study.

The common-law statement that the court adopted in People v. Navarro shows the mapping most clearly. Where no specific intent or other special mental element is required, a mistake of fact is not recognized as an excuse unless it rests on reasonable grounds.⁶⁵ Where the offense requires specific intent, as larceny does, there is "no such thing as larceny by negligence," so a taker who genuinely believes the chattel is his own is not guilty however careless the belief.⁶⁶ The Navarro defendant took beams that he believed to be worthless and abandoned, and the trial court effectively told the jury to convict unless that belief was reasonable.⁶⁷ The instruction was error, because a good-faith belief in a right to take the beams meant the specific intent to steal had not been established, and the unreasonableness of the belief mattered only as evidence that it was not genuinely held.⁶⁸ The Code reaches the same acquittal more directly, since larceny requires a purpose to deprive another of property, and an honest belief that the property is one's own or ownerless leaves no such purpose to find.⁶⁹

The common law drew its line at specific intent for reasons that are partly historical. Before the nineteenth century an honest belief excused whether or not it was reasonable, but nineteenth-century courts imported the reasonable-person standard from tort law, so that only reasonable mistakes excused. Specific-intent crimes became the exception, because defining an offense by a special mental element was read as a legislative signal that only the genuinely culpable should be convicted, and not defendants who were merely unreasonable.⁷⁰ The label thus served as a proxy for how much fault the offense demands, and the result was all or nothing: a defendant whose honest but unreasonable mistake went unrecognized was punished as though no mistake had occurred.⁷¹ The Code removes the proxy by reading the culpability term directly. The mapping runs as follows, with the common-law result first and the Code's question second.

• Specific-intent offense with an honest mistake of fact: the common law acquits however careless the belief, and the Code reaches the same result when the element carries purpose, knowledge, or belief, because an honest mistake leaves those states absent.⁷²
• Offense with no special mental element: the common law demands reasonable grounds, while the Code asks which culpability term attaches to the element, so an honest mistake suffices for knowledge or recklessness, a gross deviation is required for negligence, and a mistake helps not at all where the element carries no culpability.⁷³
• Mistake of law: the common law sorts it apart from mistake of fact and often calls it no excuse, yet it recognizes a mistake about a collateral legal matter that bears on an element, and the Code treats fact and law alike when the mistake negatives a required mental state.⁷⁴

The second bullet is where a label and the Code diverge most sharply, and a short twin makes the divergence visible.

The outcomes differ because the common law asked which label the offense wore, while the Code asks which culpability term the offense attaches to ownership. Carelessness decided the first inquiry and is irrelevant to the second unless the legislature attached negligence to the element. If it did, the defendant's mistake must fall short of a gross deviation from what a reasonable person would understand, and if it attached no culpability to ownership, the mistake negates nothing.

Classification by label is a poor substitute for reading the mental element. The label describes the offense as a whole, while a mistake bears on one element at a time, and the Code assigns culpability element by element, so generalizations about general-intent and specific-intent crimes tend to obscure the simple question of whether the mistake negates the required mental state.⁷⁷ The dissent in Short shows the cost. It explained that the majority borrowed a reasonable-belief rule from rape for assault with intent to rape, and the clearer way to state its objection drops the labels: assault with intent to rape names a purpose, which cannot coexist with an honest belief in consent, while rape, on the reading the majority relied on, contains no element of knowledge that the woman did not consent.⁷⁸ The dissent's marijuana example makes the same point. Knowing possession denotes conscious awareness of what is possessed, so even a negligent ignorance of the cigarettes' character is a defense, and a flat rule that mistakes must be reasonable fails the element's own terms.⁷⁹

On an exam, the first step is to identify which regime the question assumes, since the common-law mapping earns credit in a jurisdiction that follows it and the Code analysis earns credit where the Code governs. The usual error is translating a common-law label directly into a Code result. A general-intent offense does not automatically require a reasonable mistake under the Code, because the Code may attach recklessness to the element, and an honest mistake negates recklessness.⁸⁰ Where the question supplies the Code's text, set the labels aside and read the culpability term.