Improper Use of Magic Office

The Improper Use of Magic Office is a division of the Department of Magical Law Enforcement at the Ministry of Magic. It is headed by Mafalda Hopkirk.

Functions
The Office is responsible for investigating offences under the Decree for the Reasonable Restriction of Underage Sorcery and International Confederation of Wizards' Statute of Secrecy. The Decree prohibits an underage wizard or witch from performing magic, while the Statute of Secrecy prohibits wizards and witches from performing magic in the presence of Muggles or in a Muggle-inhabited area.

On receiving intelligence reports of a violation of the Decree, a note is sent to the offender detailing actions that will be taken by the Office. First-time offenders are usually let off with a warning while extreme cases may be referred to the Wizengamot. Thus, it appears that the Improper Use of Magic Office deals with offences that are more regulatory in nature than criminal, as the latter would be dealt with by Hit Wizards or the Auror Office. However, penalties can still be harsh.

Also, this is where the Animagus registration is posted, and that all Animagi must register with all their distinguishing traits noted, in order for them not to abuse their abilities. The registry is open to public viewing. Failing to register will receive a sentence in Azkaban.

Contact with Harry Potter
The Improper Use of Magic Office came into contact with Harry Potter repeatedly during his childhood. He received a warning letter from them when Dobby used a Hover Charm to smash a pudding on a houseguest of his Aunt and Uncle. It was assumed that Harry levitated the pudding, but Minister for Magic Cornelius Fudge let him go with a warning. One year later, Harry caused Aunt Marge to float like a balloon but Fudge let him go because he felt pity for Harry, believing Sirius Black to be on the hunt for him.

This pity turned to malice when years later, Harry received notice of expulsion from Hogwarts School of Witchcraft and Wizardry after he used a Patronus Charm against threatening Dementors in his Muggle hometown of Little Whinging. The letter informed him that his wand would be destroyed by Ministry officials and he would be detained until Court notice; this appears to be the standard procedure. Through the intervention of Albus Dumbledore, punishment and wand destruction was delayed until a Wizengamot Court could be held for Harry.

It is suggested that the Improper Use of Magic Office attends Wizengamot Court services, though when Harry Potter has a trial in 1995, nothing is mentioned about them. It is presumed that this department has several positions and that they remained loyal to the Ministry even when Cornelius Fudge denied Lord Voldemort had risen again.

Harry was indeed tried before the entire Wizengamot court, however, it was highly unusual procedure for a case of underage use of magic. The hearing was held in Courtroom Ten below the Department of Mysteries at the Ministry of Magic. Incidentally, it was the same courtroom Harry had previously visited via the Pensieve. It was a horribly intimidating room with a chair that self-locks when the defendant sits down. Amelia Bones, former head of the Department of Magical Law Enforcement, was present at this hearing.