Harry Potter: The Grim Truth About Hogwarts Professors & Unforgivable Curses

A lot of the magic found within the "Harry Potter" franchise is light-hearted and cheerful; think Hermione telling Ron that it's "wingardium levi-O-sa," not "levioSA" in "Sorcerer's Stone." There are some truly evil forms of magic, though — and unfortunately, Harry, Ron, and Hermione run afoul of pretty much all of them as they work together to bring down the Dark Lord Voldemort.

Voldemort has his own little corner of horrifying magic with his Horcruxes, pieces of his soul that can only be split apart from his physical body by committing murder in cold blood — and which Harry, Ron, and Hermione have to defeat before they can kill him — but beyond that, there's also the Unforgivable Curses. Mad Eye-Moody (or, more accurately, Barty Crouch Jr. masquerading as Mad-Eye Moody thanks to some Polyjuice Potion) teaches the gang each of them in turn in "Goblet of Fire." There's the Imperius Curse, which allows total control of its victim. The Cruciatus Curse is simple yet devastating torture. And then there's Avada Kedavra, the "Killing Spell," which cannot be blocked, stopped, or reversed.

This has led fans to ask a hard question: do the professors at Hogwarts, who are tasked with protecting young magical lives, know these curses? u/IngenuityLeading372 started a Reddit thread about this very issue, writing, "Do the professors at hogwarts IE mcgonagall, sprout, pomfrey, snape know how to use the unforgivable curses? I'm guessing they do they just can't use them, just something I'm curious about and wondering if anyone knows? Adding to that if one of the professors had used avada kedavra against Voldemort would they have been punished for it by the ministry?"

u/ImColinDentHowzTrix addressed the Mad-Eye of it all head-on, writing, "Imposter Moody was 'teaching' them to fourth years in defense against the dark arts. If we assume his methods were f**king insane but that the topic itself might still have been on the syllabus then it would be strange for the teachers (and indeed, every witch and wizard who had their fourth year at Hogwarts) to not know them. It would be like a muggle not knowing that stabbing someone through the heart would kill them – it's known, you're just not supposed to do it."

There's another thing mentioned frequently on this thread, which is that Hogwarts Potions master Severus Snape casts Avada Kedavra right in front of Harry, killing Albus Dumbledore in the process. In "Harry Potter and the Half-Blood Prince," Harry watches helplessly as Snape casts the fatal spell and Dumbledore dies before his eyes, proving that, yes, Hogwarts professors do understand the processes behind the Unforgivable Curses. Mad-Eye does note during his lesson, though, that "Avada Kedavra's a curse that needs a powerful bit of magic behind it – you could all get your wands out now and point them at me and say the words, and I doubt I'd get so much as a nosebleed." Snape is a powerful wizard, and he's able to cast it. Of course, Snape and Dumbledore had a deal, as the latter was dying anyway... but Harry doesn't know this as he watches his least favorite teacher apparently murder his mentor.

Snape might be a character a lot of people love to hate, but even Minerva McGonagall, one of the series' sternest yet most beloved figures, knows how to cast an Unforgivable Curse without issue. As u/TheReformedBadger points out on the same thread, "Yes. McGonagall used the imperious curse on Carrow in book 7," referring to a moment when Harry is searching Ravenclaw Tower only to come across Amycus Carrow, who spits in Professor McGonagall's face. Harry, for his part, uses the Cruciatus Curse on Amycus, at which point McGonagall uses Imperio, ties the man up, and the two continue in their fight to save Hogwarts from Voldemort.

So, yes — it appears that most wizards, as well as Hogwarts professors, know the Unforgivable Curses. It's even possible that sweet matriarch Molly Weasley knows Avada Kedavra, considering that she kills Bellatrix Lestrange during the Battle of Hogwarts (though it's not specified which spell she uses). In any case, wizards know better than to use these terrifying and dangerous curses, and when the "good guys" do use them, it's only in the most dire of life-or-death circumstances. Even Harry, in his final moments against Voldemort, doesn't use Avada Kedavra like his opponent; he uses the Disarming Spell to take down his lifelong foe.