Motu Proprio

The name given to certain papal rescripts on account of the clause motu proprio (of his own accord) used in the document. The words signify that the provisions of the rescript were decided on by the pope personally, that is, not on the advice of the cardinals or others, but for reasons which he himself deemed sufficient. The document has generally the form of a decree: in style it resembles a Brief rather than a Bull, but differs from both especially in not being sealed or countersigned. It issues from the Dataria Apostolica, and is usually written in Italian or Latin. It begins by stating the reason inducing the sovereign pontiff to act, after which is stated the law or regulation made, or the favour granted, It is signed, personally by the pope, his name and the date being always in Latin. (Source: New Advent / Catholic Encyclopedia https://www.newadvent.org/cathen/10602a.htm)