Also known as: mala per se · malum in se
Written by attorneys · grounded in primary & secondary sources — see below
An act or offense that is inherently immoral or wrongful by its very nature, independent of any statutory prohibition. The classification turns on whether the conduct itself carries moral blameworthiness rather than on legislative fiat alone.
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Cole chained the store's only emergency exit to deter theft despite knowing the action violated local fire codes. When faulty wiring ignited a blaze, janitor Samantha could not escape and died of smoke inhalation. Because the underlying misdemeanor was inherently wrongful, the death during its commission supported manslaughter liability without separate proof of foreseeability.
Fraternity president Mark ordered underage pledges to consume repeated shots of liquor under threat of expulsion, violating anti-hazing and alcohol laws. Pledge Jonah collapsed and died of alcohol poisoning. Because the predicate offenses were inherently wrongful, the death during their commission supported involuntary manslaughter without separate proof of foreseeability.
Investment associate Leah shoved a colleague who confronted her about unauthorized securities sales sessions. The shove caused the colleague to fall through a glass partition and bleed to death. The battery qualified as malum per se, so the resulting death during its commission supported manslaughter liability.
Supervisor Riley ordered workers to burn debris knowing the act was inherently wrongful and dangerous. Thick smoke crossed the road, causing a driver to swerve and kill cyclist Jordan. Because the underlying conduct was malum per se, the death during its commission supported manslaughter liability.
Engineer Nina flew a drone indoors in a crowded space knowing the act was inherently wrongful. The drone struck a light fixture that fell and killed attendee Carlos. Because the underlying conduct was malum per se, the death during its commission supported manslaughter liability.
Supervisor Leo ordered concrete saws to run after hours knowing the act was inherently wrongful and dangerous. The sudden noise startled resident Nora, who fell down stairs and died. Because the underlying conduct was malum per se, the death during its commission supported manslaughter liability.
When the underlying misdemeanor is malum per se, many courts impose manslaughter liability for a resulting death without requiring separate proof that the death was foreseeable. The inherent wrongfulness of the act supplies the necessary culpability. In contrast, when the misdemeanor is merely malum prohibitum, the prosecution must show that the death was a natural or foreseeable consequence of the unlawful conduct.
Supporting sources
…to note that for many years even those in favor of the rules against solicitation by attorneys agreed that solicitation was not "malum in se." H. Drinker, Legal Ethics 211 n. 3 (1953). Dr. Johnson, a venerable commentator on mores of all sorts, expressed well the prevailing view of the profession when he stated: "I should not…
…of "gross and open indecency" in Winters v. New York , 333 U. S. 507, 515 (1948). Public nudity was considered an act malum in se
…But this rule, in its application to the law of crimes, is subject to certain important exceptions. Where the act done is malum in se
…the offender, or rather the offence is attached primarily to the thing; and this, whether the offence be malum
…e.g. , a policeman or one of the felons) and the identity of the person causing the death.[^maj-50] (4) "The felony must be malum in se
Malum per se refers to conduct that is inherently immoral or evil in itself, such as murder or rape. Malum prohibitum refers to conduct that is wrongful only because a statute or ordinance forbids it, such as a regulatory fire-code violation. The distinction determines whether foreseeability of harm must be proven to support manslaughter liability under the misdemeanor-manslaughter rule.
Supporting sources
No. Regulatory offenses such as fire-code or noise-ordinance violations are treated as malum prohibitum because they lack inherent moral wrongfulness. They become the basis for manslaughter only when the resulting death is shown to be a foreseeable consequence of the violation.
Supporting sources
Yes. The classification focuses on the nature of the underlying conduct, not on the defendant's mental state regarding the resulting death. Forcing underage pledges to drink excessively or chaining an emergency exit in violation of fire codes can be malum per se or malum prohibitum regardless of whether the actor intended anyone's death.
Supporting sources