Suo motu, meaning "on its own motion," is a Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 legal term, approximately equivalent to the term sua sponte

Sua sponte

In law, sua sponte 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...

. For example, it is used where a government agency acts on its own cognizance, as in "the Commission took suo motu control over the matter." Example - "there is no requirement that a court suo motu instruct a jury upon these defenses." State v. Pierson.