The name derives from the Latin words for "before" and "to ask" or "to pray," but scholars disagree on what that originally meant. Some say the name derives from the early practice of waiting in the hallway for the king to pass by on his way to the chapel every morning and asking him to grant the writ, thus "before" his "prayers" at Mass (but this is unlikely because it seems to confuse "rogare" with "orare," although it might be that it came from "asking" "before" he went to pray). Others say it derives from the fact that the writs were not granted as a matter of right, but only if the person showed good cause, thus "asking" "before" having one granted. Still others say it derives from the writs' being among the king's exclusive discretionary powers, called his "royal prerogatives."
There are six prerogative writs:judicial review.