|This article is non-canon.
This article covers a subject that has been deemed non-canon by either the author or the Harry Potter licensees, and thus should not be taken as a part of the "real" Harry Potter universe.
- "Those wishing to join the Inquisitorial Squad for extra credit may sign up in the High Inquisitor's office."
- —The Decree[src]
The Educational Decree Number Ninety-Eight was one of the Educational Decrees created by Dolores Umbridge, then-Hogwarts High Inquisitor. This Educational Decree established the Inquisitorial Squad and that joining it would give the student extra credit. It also declared the location for signing up to be Dolores Umbridge's office. 
Behind the scenes
- As the numbering for this Educational Decree is not consistent with the numbering established in Harry Potter and the Order of the Phoenix, it cannot be considered canonical.
- Harry Potter and the Order of the Phoenix (film) (First appearance)
- Harry Potter and the Order of the Phoenix (video game)