Malfeasance: Commission of a wrongful act; evil doing; wrongful conduct.

Malicious Prosecution: An action instituted with intention of injuring the defendant and without probable cause, and which terminates in favor of the person prosecuted.

Mandamus: A writ issued by a court ordering a public official to perform an act.

Manslaughter: The unlawful killing of another without intent to kill; either voluntary (upon a sudden impulse); or involuntary (during the commission of an unlawful act not ordinarily expected to result in great bodily harm). See also murder.

Material Fact: Generally, a fact essential to a case or a defense without which said case or defense could not be supported.

Mediation: A form of alternative dispute resolution in which the parties bring their dispute to a neutral third party, who helps them agree on a settlement.

Medical Malpractice: Broadly, a claim brought against a health-care professional based on professional negligence wherein the health-care professional violates the applicable standard of care and an injury results.

Member: In relation to health care, a member is a person who belongs to a health care plan, like an HMO

Memorialized: In writing.

Mens Rea: The "guilty mind" necessary to establish criminal responsibility.

Mental Anguish: Mental suffering. In some cases, damages may be awarded for mental anguish even though no physical injury is present.

Miranda Warning: Requirement that police tell a suspect in their custody of his or her constitutional rights before they question him or her. So named as a result of the Miranda v. Arizona ruling by the U.S. Supreme Court.

Misdemeanor: Crimes less serious than felonies. In Pennsylvania, the punishments associated with misdemeanors vary according to degree. A misdemeanor of the first degree may be sentenced to a term of imprisonment of not more than five years. A misdemeanor of the second degree may be sentenced to a term of imprisonment of not more than two years. A misdemeanor of the third degree may be sentenced to a term of imprisonment of not more than one year.

Misfeasance: Improper performance of a lawful act.

Mistrial: An invalid trial, caused by fundamental error. When a mistrial is declared, the trial must start again from the selection of the jury.

Mitigating Circumstances: Those which do not constitute a justification or excuse for an offense but which may be considered as reasons for reducing the degree of blame.

Mitigation of Damages or Doctrine of Avoidable Consequences: Imposes a duty on victims of a tort to take reasonable steps to minimize their damages after an injury has been inflicted.

Mittimus: The name of an order in writing, issuing from a court and directing the sheriff or other officer to convey a person to a prison, asylum, or reformatory, and directing the jailer or other appropriate official to receive and safely keep the person until his or her fate shall be determined by due course of law.

Moot: A moot case or a moot point is one not subject to a judicial determination because it involves an abstract question or a pretended controversy that has not yet actually arisen or has already passed. Mootness usually refers to a court's refusal to consider a case because the issue involved has been resolved prior to the court's decision, leaving nothing that would be affected by the court's decision.

Motion: An application made to a judge for the purpose of obtaining an order directing some act to be done in favor of the party presenting the application.

Moving Party: The party presenting the motion. Compare with non-moving party.

Murder: The unlawful killing of a human being with deliberate intent to kill. Murder in the first degree is characterized by premeditation; murder in the second degree is characterized by a sudden and instantaneous intent to kill or to cause injury without caring whether the injury kills or not. (See also manslaughter.)