Are there magic-users with disabilities in the Harry Potter world?

Question

I was wondering what would happen if someone who was mentally disabled could use magic. Would they get as much of a full magic training they could handle? Or would they be trained to minimize it?

I'm going to generalize the question to either mental or physical disabilities (like blindness or deafness). Note I generally mean someone born with the disability (either genetic or birth-defect), not someone who acquired it later in life (like Neville's parents, or the protagonist at the end of the Empire Strikes Back).

Answer 1

During a press conference in 2005: She mentioned a character named Mopsus, who was blind. Although, he never made the final cut...

Richard Wheatley for the RNIB - Blind children everywhere are delighted that they can read this book at the same time as sighted people, would you ever include a blind character in one of your Harry Potter books?

JK Rowling: Funny you should say that because at one point there was a blind character who went by the name of Mopsus, and I will let you look him up because there is a mythological connection there, but he sort of ­­ that was a very early character and he had the power of second sight, in other words he was a bit like Professor Trelawney, he was a very, very early character, this was when I was drafting Philosopher's Stone, the reason I cut him was he was too good. As the story evolved, if there was somebody who really could do divination at the time that Harry was alive, it greatly diminished the drama of the story because someone out there knew what was going to happen.

So that is why Mopsus went and I have never really replaced him, although I suppose Mad-Eye Moody, had some of Mopsus' characterisation. He has one magical eye because he lost an eye in a fight with a Death Eater, so good question.

Answer 2

Mentally challenged people were normally sent to St Mungo's Hospital for Magical Maladies and Injuries. There are two instance I can think of in the books.

Gilderoy Lockhart after his training:

“Oh, my goodness," said Hermione suddenly, sounding breathless. "Professor Lockhart!"

Their ex-Defence Against the Dark Arts teacher pushed open the doors and moved towards them, wearing a long lilac dressing gown.

"Well, hello there!" he said. "I expect you'd like my autograph, would you?'

"Hasn't changed much, has he?" Harry “muttered to Ginny, who grinned.

"Er — how are you, Professor?" said Ron, sounding slightly guilty. It had been Ron's malfunctioning wand that had damaged Professor Lockhart's memory so badly that he had landed in St Mungo's in the first place, though as Lockhart had been attempting to permanently wipe Harry and Ron's memories at the time, Harrys sympathy was limited.

_{^{Harry Potter and the Order of the Phoenix, Chapter 23 - Christmas on the Closed Ward}}

Ariana Dumbledore before training:

“And my father went after the bastards that did it,” said Aberforth, "and attacked them. And they locked him up in Azkaban for it. He never said why he'd done it, because the Ministry had known what Ariana had become, she'd have been locked up in St. Mungo's for good. They'd have seen her as a serious threat to the International Statute of Secrecy, unbalanced like she was, with magic exploding out of her at moments when she couldn't keep it in any longer.”

_{^{Harry Potter and the Deathly Hallows, Chapter 28, The Missing Mirror}}

Because of the International Statute of Secrecy, mentally challenged people are sent to St Mungo's Hospital for Magical Maladies and Injuries.

Answer 3

Prof. Remus Lupin's disability was he was a werewolf. Because of this disability, he could not secure any job for him. An excerpt from Pottermore,

The downfall of Voldemort, such a source of jubilation to the rest of the wizarding community, marked the beginning of a long stretch of loneliness and unhappiness for Remus. He had lost his three close friends and, with the Order disbanded, his previous comrades returned to busy lives with families. His mother was now dead, and while Lyall, his father, was always delighted to see his son, Remus refused to endanger his father’s peaceful existence by returning to live with him.

Remus now lived a hand-to-mouth existence, taking jobs that were far below his level of ability, always knowing that he would have to leave them before his pattern of growing sick once a month at the full moon was noticed by his workmates.

Prof. Remus Lupin was persuaded by Dumbledore to be DADA professor when headmaster Prof. Dumbledore explained that there would be a limitless supply of Wolfsbane Potion at Hogwarts, courtesy of the Potions master, Prof. Severus Snape.

Alternate theories:

(i) When Peter Pettigrew cut his arm to resurrect Voldemort, temporarily, he also had become disabled.

(ii) Any person under the influence of Imperius curse can also be called as disabled.