The term illegal means any action which is against or not authorized by the law or statute. Also called illicit or unlawful.
It can refer to an action that is in violation of criminal law, like assault, arson, or murder. The action against federal criminal law or state’s penal law may be characterized as “felonies” and “misdemeanors”yet not all illegal actions will be punishable under criminal law. An illegal action which violates the public policy or civil legal obligation will not be recognized under criminal law.
[Last updated in March of 2022 by the Wex Definitions Team]