The Decree for the Reasonable Restriction of Underage Sorcery is a bylaw of the Ministry of Magic, written in 1875, which bans the use of underage magic outside of school.

The Decree is enforced by the Improper Use of Magic Office in the Ministry of Magic. The restriction is for wizards and witches who are under the age of seventeen, upon which The Trace still operates. Even so, the Ministry does recognize that they may have to use magic in certain situations such as self-defense in a life-threatening situation.

In addition, young children below school age, or children who are not in possession of a wand, are mostly exempt from the rule since they usually have little or no control over the magic they perform. Overall, it appears the Ministry of Magic generally limits enforcement of the decree to situations where underage wizards perform magic in front of Muggles.

Known Contents

"In the matter of Harry Potter, the law clearly states that magic can be used before Muggles in life-threatening situations."
—Albus Dumbledore at Harry Potter's hearing

Paragraph C of the clause states that it is a crime to knowingly perform magic in a Muggle-inhabited area and in the presence of a Muggle. However, Clause 7 also states that magic can be used in front of Muggles in exceptional circumstances, including situations when the life of the witch or wizard is threatened, or the lives of other witches, wizards and Muggles are threatened.

It seems that a high-authority person may give permission for an underage student to perform magic under circumstances; as Hogwarts Headmaster, Albus Dumbledore gave Harry Potter such an instruction if an attack was to eventuate when he was 16 years old. Also, if an underage student unintentionally performed magic out of emotional stress, the Ministry may consider this to be accidental magic, and not punish said student, as Dumbledore noted that even the best of adult wizards cannot always control their emotions,[1] and Fudge did somewhat take this into account when he spoke to Harry about it.

The use of objects already enchanted by someone else does not count as a violation, as stated by Ronald Weasley, at that time aged 12, when he and his brothers Fred and George, aged 14, used their father's flying Ford Anglia during the summer holidays.

Consequences of the Breaches

Any student who performs magic before they age is subject to either an expulsion or a disciplinary hearing. If the student has not taken their OWL's will have their wand broken by Ministry.

Offender Crime Date Action taken Notes
Lilly Evans Magic Between 1971 and early January 1977 Received a few warning letters None of her warning letters were “too serious”.
Hermione Granger "A few simple spells" Summer of 1991 No action is taken Hermione told Harry Potter and Ron Weasley just prior to their first year at Hogwarts that she had successfully cast a few spells, but because of the unknowing of the law, the breach was excused.
Harry Potter Illegal use of a Hover Charm July 31, 1992 Official warning The Hover Charm was actually produced by the House-elf Dobby.
Harry Potter Illegal use of the Inflating Charm on Marjorie Dursley August 6, 1993 No action is taken Warning not given due to the escape of Sirius Black, and protection is the priority.
Harry Potter Illegal use of the Patronus Charm in front of a Muggle August 2, 1995 Expelled from Hogwarts, later changed due to hearing and cleared of charges. Acquitted of all charges due to the fact that he technically did not break any laws. Dolores Umbridge was the one who secretly orchestrated this incident as part of the smear campaign against Harry.
Harry Potter Used Killing Curse in the presence of a muggle March 29, 2018 Expelled, but attempted to enter anyway When Vernon blames Harry for blowing up Marge, he got mad and killed Vernon.
Peppa Pig Used magic when playing Sardines with her cousin and two muggle-born friends. April 22, 2018 No action is taken When Peppa played with her cousin with her "muggle-born" friends, Peppa plays a game based on the practice of underage magic.