Legal action

In legal terminology, a complaint is any formal legal document that sets out the facts and legal reasons (see: cause of action) that the filing party or parties (the plaintiff(s)) believes are sufficient to support a claim against the party or parties against whom the claim is brought (the defendant(s)) that entitles the plaintiff(s) to a remedy (either money damages or injunctive relief). For example, the Federal Rules of Civil Procedure (FRCP) that govern civil litigation in United States courts provide that a civil action is commenced with the filing or service of a pleading called a complaint. Civil court rules in states that have incorporated the Federal Rules of Civil Procedure use the same term for the same pleading.

In some jurisdictions, specific types of criminal cases may also be commenced by the filing of a complaint, also sometimes called a criminal complaint or felony complaint. All criminal cases are prosecuted in the name of the governmental authority that promulgates criminal statutes and enforces the police power of the state with the goal of seeking criminal sanctions, such as the State (also sometimes called the People) or Crown (in Commonwealth realms). In the United States, the complaint is often associated with misdemeanor criminal charges presented by the prosecutor without the grand jury process. In most U.S. jurisdictions, the charging instrument presented to and authorized by a grand jury is referred to as an indictment.

Virtually every U.S. state has some forms available on the web for most common complaints for lawyers and self-representing litigants; if a petitioner cannot find an appropriate form in their state, they often can modify a form from another state to fit his or her request. Several United States federal courts publish general guidelines for the petitioners and Civil Rights complaint forms.

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Wikipedia