Detention

A detention is a common form of punishment for students at Hogwarts School of Witchcraft and Wizardry. Assigned by professors or other staff members for rule-breaking, detentions are intended to serve as a corrective measure. Unlike detentions in Muggle schools, those in the wizarding world can range from merely tedious chores to tasks that are genuinely dangerous or, in extreme cases, physically harmful. The nature of the detention often reflects the severity of the infraction or the disposition of the staff member assigning it.

Detentions are typically carried out in the evenings after classes have concluded. Authority to assign detention rests with Hogwarts staff, including the Headmaster, Heads of House, professors, and the Caretaker. Student leaders like Prefects can take points but their ability to assign detentions is not explicitly confirmed in the novels; however, members of the Inquisitorial Squad under Dolores Umbridge were granted this power. The assigned tasks vary widely and often serve a practical purpose for the school. Common types of detentions include:

• Tedious Manual Labour: These tasks are time-consuming and often done without the aid of magic. Examples include polishing the silver in the Trophy Room, cleaning bedpans in the Hospital Wing, scrubbing cauldrons, sorting rotten potion ingredients, or answering a professor's fan mail.
• Dangerous Assignments: The most notable example of a dangerous detention is being sent into the Forbidden Forest at night. This punishment was assigned to Harry Potter, Hermione Granger, Neville Longbottom, and Draco Malfoy in their first year.
• Lines: A seemingly traditional punishment, this could be twisted into a form of torture. Professor Dolores Umbridge famously used a Black Quill for her detentions, a dark magical object that forced the user to write lines in their own blood, leaving permanent scars. This was considered a cruel and highly unusual abuse of authority.
• Administrative Tasks: On at least one occasion, a detention involved sorting and copying old school records. Harry Potter was assigned this task by Severus Snape in his sixth year.

Throughout the series, several detentions are pivotal to the plot or character development.

• 1991-1992 School Year: Harry Potter, Hermione Granger, Neville Longbottom, and Draco Malfoy were given detention for being out of their dormitories after hours. They were sent into the Forbidden Forest with Rubeus Hagrid to find a wounded Unicorn. During this detention, Harry had his first direct encounter with the wraith-like form of Lord Voldemort.
• 1992-1993 School Year: Harry was given detention by Gilderoy Lockhart and forced to help answer his voluminous fan mail. It was during the quiet of this detention that Harry first heard the disembodied voice of the Basilisk moving through the castle's plumbing.
• 1992-1993 School Year: Ron Weasley served detention with Argus Filch, polishing all the silver in the Trophy Room without magic as punishment for crashing his father's flying Ford Anglia into the Whomping Willow.
• 1995-1996 School Year: Harry was subjected to a series of detentions with High Inquisitor Dolores Umbridge for contradicting her Ministry-approved version of events concerning Lord Voldemort's return. In these sessions, he was forced to use her Black Quill, which carved the words “I must not tell lies” into the back of his hand, leaving a permanent scar.
• 1996-1997 School Year: After using the Sectumsempra curse on Draco Malfoy, Harry was given Saturday detentions for the remainder of the school year by Severus Snape. His task was to organize and copy out the old detention records for Argus Filch, including the files on his father, James Potter, and Sirius Black. This punishment caused him to miss the final Quidditch match of the season.
• 1997-1998 School Year: Under the control of the Death Eaters, punishments at Hogwarts became brutal. However, when Neville Longbottom, Ginny Weasley, and Luna Lovegood were caught attempting to steal the Sword of Gryffindor, their punishment from the Carrows was a detention with Hagrid in the Forbidden Forest, an outcome they considered a relief compared to the usual practice of being tortured with the Cruciatus Curse.

• In the film adaptation of Harry Potter and the Order of the Phoenix, the cruelty of Dolores Umbridge's detentions is emphasized visually. After Harry has written with the Black Quill, Umbridge physically grabs his hand and inspects the bleeding wound with a satisfied expression, a detail not explicitly described in the book. (film)