"This is not the first time in recent weeks that the Minister, Cornelius Fudge, has used new laws to effect improvements at the wizarding school. As recently as 30ih August, Educational Decree Number Twenty-two was passed, to ensure that, in the event of the current Headmaster being unable to provide a candidate for a teaching post, the Ministry should select an appropriate person."
-- from the Daily Prophet, 8 September 1995
This decree allows the Ministry to appoint a Defence Against the Dark Arts professor since Dumbledore has not yet found one. Fudge chooses Dolores Umbridge.