As any fan of the franchise worth their salt can tell you if asked, the biggest and most important responsibility of the fictional Ministry of Magic in J. K. Rowling’s universe is to make sure people like you and me (Muggles) remain blissfully ignorant of the continued existence of magic. This is where the Improper Use of Magic Office comes in: It is a section of the Department of Magical Law Enforcement that reoccurs throughout most of the Harry Potter series whenever Harry has used magic outside of school without permission. But what exactly is it that they do?
Well, they write letters… we know that much.. When Harry uses magic illegally, or someone uses magic near Harry, thus triggering the “Trace” that alerts the Ministry to the spell used, he is issued these warning letters from the Improper Use of Magic Office. In the fifth book, admittedly, it takes some liberties in regard to what the Ministry of Magic can and cannot do, as it announces Harry’s expulsion before Harry was expelled, for example. but what else? What exactly is it that this office does that is so important?
I think I have figured that out. We have been presented several other subdivisions in the aforementioned Department that all are tasked with what one might call “improper” use of magic. The Misuse of Muggle Artefacts Office deals with people who put spells on non-magical objects. There is the Office for the Detection and Confiscation of Counterfeit Defensive Spells and Protective Objects to which Arthur was promoted to oversee in the sixth book, doing exactly what the name implies. And we have the Office for the Removal of Curses, Jinxes, and Hexes, which breaks through curses, jinxes and hexes. All of these are merely denote various degrees of Dark Magic placed on magical objects, if we for the sake of this essay we agree Dark Magic is all magic used with malicious intent.
All of these examples are of “improper” use of magic, yet – why are there so many offices when there already is an office for Improper Use of Magic? Aren’t the others redundant? I wouldn’t say so. For me, it looks more like the Improper Use of Magic Office is the figurative “face” of the Ministry’s efforts to uphold law and order in regard to wizarding secrecy. In short, the Improper Use of Magic Office is the “official” branch, that is the first one to be informed about misuse of magic and delegates the practical and regulatory aspects of the job to the relevant subsection depending on the type of misuse, while the actual office takes much of the credit and attends to the judicial part, as well as maintain written correspondence with the involved parties, including notifying the Department of Magical Accidents and Catastrophes if required.
The reason for why I think this can be found in the fourth book. Arthur Weasley is informed by Amos Diggory through the Floo Network that the Improper Use of Magic Office are about to seek out Alastor Moody and quite possibly arrest him for violating the Statute of Secrecy. Moody was seen by the Muggle police jinxing the dustbins outside his house to run amok and spew garbage everywhere. Arthur told Amos that if he could get there first, it would be his case, so he would be free to merely give Moody a warning for the transgression. I always wondered how/why he could do that without the Improper Use of Magic lot claiming jurisdiction and sending Arthur back to the Ministry, especially since the position he held did not exactly enjoy much respect among his colleagues. Then it dawned on me that if they could not claim jurisdiction, it could only be one reasonable explanation as to why that is: Rather than working independently from one another, the three offices above are subsections of the Improper Use of Magic Office, and thus in the larger scheme of things, representing it. For them to try to pull rank on Arthur would be like trying to pull rank on themselves. And it is concepts like this that makes me think the Ministry in some ways are a far more complex a structure than we might give it credit for.