The difference between the status of different papal documents can sometimes appear to be an esoteric affair. A brief (from the Latin breve, i.e., "short") was a papal letter which dispensed with some of the formalities previously insisted upon in papal bulls. Papal briefs were introduced in the 15th Century by Pope Eugenius IV. Written on vellum, generally folded, it is sealed in red wax with the papal ring of the fisherman. The Pope's name appears at the top, normally written in capital letters, e.g.: PIUS PP III; instead of the formal salutation in the third person used in bulls.
A papal brief adopts a direct form of address, and begins by way of preamble with a statement of the case and cause of the brief. Seen as less formal and binding than a papal bull, bulls continued to be employed—for example in canonizations. In granting the dispensation which enabled Henry VIII Tudor to marry his brother's widow, Catherine of Aragon, two forms of dispensation were issued by Julius II, one a brief, seemingly expedited in great haste, and the other a bull which was sent on afterwards. Similarly we may notice that, while the English Catholic hierarchy was restored in 1850 by a brief, Pope Leo XIII in the first year of his reign used a bull to establish the Catholic episcopate of Scotland.
The drawing up of the Brief of Suppression, Dominus ac Redemptor, bypassed some of the normal protocol expected for the publication of a Papal Brief. Normal procedure would involve an announcement of the brief in Campo de Fiori and copies placed in placards at the gates of the Vatican. This time the brief that would supress the Jesuits, would be surrounded in strictly controlled secrecy. The Pope bound those involved with its production to absolute secrecy under pain of excommunication.