A procedure which calls upon a party to show cause as to why a proposed rule should be applied by the court. Generally, a rule nisi is an order “to show cause” , meaning that the ruling is absolute unless the party to whom it applies can show cause why it should not apply. In divorce cases, a rule nisi is issued by the court to tell the parties that they have to wait a certain period of time before making their divorce final. This is to allow time for anyone who objects to the divorce to tell the court why they object. The rule nisi can often be set aside with mutual consent of the spouses. When the period expires, they can apply for the "decree absolute", which means the divorce is completed and the partners are no longer married. it is also called a decree nisi. Some states grant divorces using decrees nisi. The following is an example of a state statute involving decrees nisi:
§ 554. Decrees nisi
(a) A decree of divorce from the bonds of matrimony in the first instance, shall be a decree nisi and shall become absolute at the expiration of three months from the entry thereof but, in its discretion, the court which grants the divorce may fix an earlier date upon which the decree shall become absolute. If one of the parties dies prior to the expiration of the nisi period, the decree shall be deemed absolute immediately prior to death.
(b) Either party may file any post-trial motions under the Vermont Rules of Civil Procedure. The time within which any such motion shall be filed shall run from the date of entry of the decree of divorce and not from the date the nisi period expires. The court shall retain jurisdiction to hear and decide the motion after expiration of the nisi period. A decree of divorce shall constitute a civil judgment under the Vermont Rules of Civil Procedure.
(c) If the stated term at which the decree nisi was entered has adjourned when a motion is filed, the presiding judge of the stated term shall have power to hear and determine the matter and make new decree therein as fully as the court might have done in term time; but, in the judge's discretion, the judge may strike off the decree and continue the cause to the next stated term.
A decree nisi (non-absolute ruling) is a ruling by a court that does not have any force until such time that a particular condition is met. Once the condition is met the ruling becomes decree absolute and is binding. Typically, the condition is that no new evidence or further petitions with a bearing on the case are introduced to the court.
This form of ruling has become a rarity in recent times, with one exception—in some jurisdictions it is still a standard stage of divorce proceedings. In the United Kingdom one judge approved 34 decrees nisi in just over a minute. This allows time for any party who objects to the divorce to come forward with those objections. It is also at times termed as rule nisi. In most common law jurisdictions, a decree nisi must be obtained in possession proceedings before the court will order foreclosure under a mortgage enforcement.