What is a complaint in legal proceedings?

A complaint in legal proceedings is fundamentally a formal document that initiates a lawsuit. It serves as a written allegation that specifies the legal claims against a defendant and outlines the grounds for the court's jurisdiction, the facts of the case, and the demands for relief. In the context of criminal cases, a complaint specifically refers to a formal charge made by a prosecuting entity alleging that an individual engaged in criminal activity. This document is essential in outlining the nature of the offense and provides the defendant with notice of the charges they face.

In contrast, a request for a change of venue pertains to the desire to move a trial to a different location, driven by concerns such as bias or convenience. An affidavit supporting an indictment refers to a sworn statement used to justify the issuance of an indictment but does not itself constitute a complaint. Lastly, a statement of defense provided by the accused outlines their response to the charges rather than detailing the initial allegations against them. Therefore, the function and essence of a complaint as a formal charge that alleges criminal activity is accurately captured by the correct answer, making it the appropriate choice in this context.