- 1: to express grief, pain, or discontent <complaining about the weather>
- 2: to make a formal accusation or charge
In legal terminology, a complaint is a 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 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.
In many U.S. jurisdictions, a complaint submitted to a court must be accompanied by a Case Information Statement, which sets forth specific key information about the case and the lawyers representing the parties. This allows the judge to make determinations about which deadlines to set for different phases of the case, as it moves through the court system.
In some countries, (for example Australia and the UK and many countries of the European Community), the making of consumer complaints, particularly regarding the sale of financial services, is governed by statute. The statutory authority may require companies to reply to complaints within set time limits, publish written procedures for handling customer dissatisfaction and provide information about arbitration schemes.