A motion to quash is a request to the court to end enforcement of a court order or declare the order invalid. It can also refer to a request to a court or other tribunal to render a previous decision or proceeding null or invalid. The exact usage of motions to quash depends on the rules of the particular court or tribunal. In some cases, motions to quash are requests to nullify a decision made by the same or a lower court. It can arise out of mistakes made by any lawyer or court officer. A lawyer may file a motion to quash if a mistake has been made on the part of a court, or if an attorney believes that some court document such as a subpoena was not issued or delivered following the required procedure.

In the context of a court hearing an appeal, depending on the rules of the court, a motion to quash the appeal may be made on the basis that the court has no jurisdiction. A motion to quash service specifically states that a party to a court case was NOT properly served notice of the court case. The motion must be signed by a public notary. For a motion to quash service to be considered, a person must be able to prove that they were never properly served a notice of summons for the case, no one over the age of 13 was present at their residence when a summons was served, and they never filed an appearance for the case.

In summary, a motion to quash is a legal request to end enforcement of a court order or declare the order invalid, or to render a previous decision or proceeding null or invalid. It can also refer to a request to nullify a decision made by the same or a lower court, or to challenge the entire basis for a lawsuit. The exact usage of motions to quash depends on the rules of the particular court or tribunal.