Which document is utilized to initiate a lawsuit in federal court?

The document utilized to initiate a lawsuit in federal court is the complaint. A complaint serves as the formal legal document that outlines the plaintiff's allegations against the defendant and the legal basis for the court's jurisdiction. It specifies the claims being made, the facts supporting those claims, and the relief or damages sought.

In federal court, the complaint must be filed with the appropriate court and then served on the defendant, effectively starting the legal proceedings. It provides the framework for the case and alerts the defendant to the nature of the claims and the plaintiffs' arguments.

Other documents play significant roles within the litigation process but do not serve to initiate a lawsuit. A motion is usually a request made to the court on a specific matter during the course of litigation, while a petition is often used in different contexts, such as in certain types of court proceedings or in state court. A response typically refers to the defendant's reply to the complaint or a motion, further developing the legal arguments but not commencing a lawsuit.