Malum

adj. Lat. Wrong; evil; wicked reprehensible.

— Malum in se. A wrong in itself; an act or case involving illegality from the very nature of the transaction, upon principles of natural, moral, and public law. Story, Ag. § 346. An act is said to be malum in se when it is inherently and essentially evil, that is, immoral in its nature and injurious in its consequences, without any regard to the fact of its being noticed or punished by the law of the state. Such are most or all of the offenses cognizable at common law, (without the denouncement of a statute;) as murder, larceny, etc.

— Malum prohibitum. A wrong prohibited; a thing which is wrong because prohibited; an act which is not inherently immoral, but becomes so because its commission is expressly forbidden by positive law; an act involving an illegality resulting from positive law. Contrasted with malum in se. Story, Ag. § 346.