In United States law, a motion is a procedural device to bring a limited, contested issue before a court for decision. It is a request to the judge (or judges) to make a decision about the case. Motions may be made at any point in administrative, criminal or civil proceedings, although that right is regulated by court rules which vary from place to place. The party requesting the motion may be called the movant, or may simply be the moving party. The party opposing the motion is the nonmovant or nonmoving party.
In the United States, as a general rule, courts do not have self-executing powers. In other words, in order for the court to rule on a contested issue in a case before it, one of the parties or a third party must raise an appropriate motion asking for a particular order. Some motions may be made in the form of an oral request in open court, which is then either summarily granted or denied orally by the court. Today, however, most motions (especially on important or dispositive issues that could decide the entire case) are decided after oral argument preceded by the filing and service of legal papers. That is, the movant is usually required to serve advance written notice along with some kind of written legal argument justifying the motion. The legal argument may come in the form of a memorandum of points and authorities supported by affidavits or declarations. Some northeastern U.S. states have a tradition in which the legal argument comes in the form of an affidavit from the attorney, speaking personally as himself on behalf of his client. In contrast, in most U.S. states, the memorandum is written impersonally or as if the client were speaking directly to the court, and the attorney reserves declarations of his own personal knowledge to a separate declaration or affidavit (which are then cited to in the memorandum). One U.S. state, Missouri, uses the term "suggestions" for the memorandum of points and authorities.
Either way, the nonmovant usually has the opportunity to file and serve papers opposing the motion. In addition, most jurisdictions allow for time for the movant to file reply papers rebutting the arguments made in the opposition.
Customs vary widely as to whether oral argument is optional or mandatory once briefing in writing is complete. Some courts issue tentative rulings (after which the loser may demand oral argument) while others do not. Depending upon the type of motion and the jurisdiction, the court may simply issue an oral decision from the bench (possibly accompanied by a request to the winner to draft an order for its signature reducing the salient points to writing), take the matter under submission and draft a lengthy written decision and order, or simply fill out a standard court form with check boxes for different outcomes. The court may serve all parties directly with its decision or may serve only the winner and order the winner to serve everyone else in the case.