What legal document is issued to notify a party of a court action?

The correct answer is a summons because it is the legal document specifically issued to notify a party that a court action has been initiated against them. A summons serves to inform the defendant of the lawsuit and compels them to respond or appear before the court by a certain deadline. This document is essential in ensuring that the due process rights of the parties involved are upheld, thus providing notice of the action and allowing the defendant an opportunity to defend themselves.

In contrast, a subpoena is used to command a person to appear in court or produce documents in a case, but it does not notify a party of a court action against them. A complaint is the legal document that outlines the plaintiff's case and claims against the defendant but is not the instrument used to notify the defendant of the action itself. An affidavit is a sworn statement used as evidence in court, but it does not serve the purpose of notifying a party of a court action. Each of these documents plays a distinct role in legal proceedings, but the summons is specifically designed for the notification of a lawsuit.