Suo motu

In law, sua sponte (Latin: "of his, her, its or their own accord") or suo motu "on its own motion" describes an act of authority taken without formal prompting from another party. The term is usually applied to actions by a judge taken without a prior motion or request from the parties. The form nostra sponte ("of our own accord") is sometimes used by the court itself, when the action is taken by a multi-member court, such as an appellate court, rather than by a single judge (third parties describing such actions would still refer to them as being taken by the court as a whole and therefore as 'sua sponte'). While usually applied to actions of a court, the term may reasonably be applied to actions by government agencies and individuals acting in official capacity.

One situation in which a party might encourage a judge to move sua sponte occurs when that party is preserving a special appearance (usually to challenge jurisdiction), and therefore cannot make motions on its own behalf without making a general appearance. Common reasons for an action taken sua sponte are when the judge determines that the court does not have subject-matter jurisdiction or that the case should be moved to another judge because of a conflict of interest, even if all parties disagree.

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