(A) The erroneous performance of a legal action, most commonly used to refer to a professional person or public official commites an error or improper action that is not illegal. For example, a lawyer who commits legal malpractice by negligently filing papers after the due date. (B) torts, contracts. The performance of an act which might lawfully be done, in an improper manner, by which another person receives an injury. It differs from malfeasance, or, nonfeasance. 2. It seems to be settled that there is a distinction between misfeasance and nonfeasance in the case of mandates. In cases of nonfeasance, the mandatary is not generally liable, because his undertaking being gratuitous, there is no consideration to support it; but in cases of misfeasance, the common law gives a remedy for the injury done, and to the extent of that injury. (C)
Law Dictionary – Alternative Legal Definition
A misdeed or trespass. The doing what a party ought to do improperly. 1 Tidd, Pr. 4. The improper performance of some act which a man may lawfully do. Misfeasance, strictly, is not doing a lawful act in a proper manner, omitting to do it as it should be done; while malfeasance is the doing an act wholly wrongful; and non-feasance is an omission to perform a duty, or a total neglect of duty. But “misfeasance” is often carelessly used in the sense of “malfeasance.”