Content Note/Trigger Warning: Discussion of torture, murder, mind control, consent, and so on.

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Let's talk about the Unforgivable Curses.

More specifically, let's talk about how they work, and what their designation as "Unforgivable" says about Wizarding culture.

They are introduced to us as "the Three Unforgivable Curses" in Goblet of Fire, by Defense Against the Dark Arts professor Alastor Moody, former Auror and really Death Eater Bartemius "Barty" Crouch, Jr. in disguise. These are the three curses whose use Crouch-as-Moody introduces them to us in this order: The Imperius Curse, the Cruciatus Curse, and Avada Kedavra, the Killing Curse.

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1. The Imperius Curse

The Imperius Curse is given to us as a means of mind control. It places the victim under a strong mental suggestion encouraging them to do what the caster wants. It is difficult to break free of; it is suggested that one must possess a very strong will in order to break free. Under the Imperius Curse, depending on how strong the caster's hold over the victim is, the victim can be made to do anything: commit acrobatic feats they would normally be incapable of, commit torture and espionage, commit murder and suicide. During the First Wizarding War, the Imperius Curse was a huge problem for the Ministry of Magic, because thanks to its influence, they couldn't be sure who had betrayed them of their free will, and who had not.

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2. The Cruciatus Curse

The Cruciatus Curse is the torture curse: with it and a sufficient desire to inflict pain, the caster can indeed inflict unbearable pain on their victim. As I have said, the key to successfully performing the Cruciatus Curse is the desire to harm. It is not enough to simply be angry with someone; you have to want to hurt them, want to hear them scream, want to see them huddled in a ball at your feet sobbing uncontrollably. This was the curse used by Bellatrix Lestrange and others to torture Frank and Alice Longbottom into insanity.

I have my (as far as I know, completely non-canonical) theory about how this curse works, and how it can make you end up like the Longbottoms. My suspicion is that the Cruciatus Curse works by exciting the nerve cells in the brain in an effort to "tricking" the brain into thinking that the body is truly being sufficiently injured to cause the sort of pain inflicted by the Cruciatus Curse, and thus sending signals down to the nerves throughout your body that you are being injured, and should feel pain. It is, perhaps, the opposite of how recognition of pain works in real life. In real life, if you press your finger onto a hot stove, pain is instantaneous, and the nerves in your finger will very quickly send a signal to your central nervous system that what you are doing is injurious and you should take your hand off the stove.

As to how this can make you end up like the Longbottoms, my guess is that the Cruciatus Curse causes brain damage. I have no idea if this is actually plausible in real life; I also have no idea of how it can turn your hair white (Given that Neville's mother probably wasn't old enough to have white hair by the time he was fifteen). However, who knows? Maybe magic can make your brain work this way. All we really have is what the Cruciatus Curse does to you; we don't know how it does it.

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3. The Killing Curse

The Killing Curse, known as Avada Kedavra, is the final Unforgivable Curse. As you can gather from its name, Avada Kedavra is used to kill people. Similar to the Cruciatus Curse, you can't just scream "Avada Kedavra!" at the drop of a hat and expect it to work for you: "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," Crouch-as-Moody tells us in Goblet of Fire (217). The Killing Curse requires both strength of magic and strength of will—you need to really, truly want to kill someone in order to make the spell work.

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What is it about these three curses that makes Wizarding society* think of them as Unforgivable? Why them and not others? After all, Avada Kedavra isn't the only spell that can kill you; the Severing Charm, the Reductor Curse (which has been known with a sufficiently powerful caster to reduce a table to a pile of dust; imagine what that could do to human flesh), and Snape's Sectumsempra can all potentially cause serious death or injury. It can be argued that Avada Kedavra is considered Unforgivable because it is the only one that was created with the specific intent to kill (And that in the case of Sectumsempra, which is also only ever meant to inflict harm, that it isn't widely enough known to be on the radar). You can give any number of arguments for why it is these three curses, and not others, that have been deemed Unforgivable, but I'm thinking of one in particular.

I think that there is a reason that Wizarding society named above all other curses the Mind Control Curse, the Torture Curse, and the Killing Curse as the Three Unforgivable Curses, whose use can land you in prison for the rest of your life. I also believe that this choice says something very important about Wizarding society. Because think about it. What is the one thing that these three curses, these three Unforgivable Curses, all have in common.

They are all about the negation of volition.

They are all about the removal of free will.

These three curses are the ones that can and are used to make other people do what the caster wants, stomping on their consent and free will in the process. With them, you can make anyone do what you want, either through coercion, torture, or by threat of murder. You can use the Imperius Curse to coerce and mind control someone into doing your bidding. You can use the Cruciatus Curse to torture someone into doing what you want. You can make someone obey you by hanging the threat of the Killing Curse over their heads, and you can kill them with it if they won't do what you want.

What does that say about the Wizarding World? I think it says that all that is good and right in the Wizarding World values free will very highly.

Voldemort, the main villain of the Harry Potter series, seeks to dominate and control. He casts the Imperius Curse to make people who would never have followed him of their own free will clamor under his banner. He uses the Cruciatus Curse (and his followers, taking their cues from him, do the same thing) in order to get information, to punish erring followers, and to coerce others into following him. He uses the Killing Curse to silence defiant enemies and neutralize the potential threat these enemies pose to him (The Potters, anyone)?

Barty Crouch, Sr., who is presented as Voldemort's literary opposite and twisted reflection in many ways, also seeks to dominate and control. He is presented less as a crazed, homicidal sorcerer intent on conquering the Wizarding World, and more as a man who seeks to control Wizarding society "for its own good." During the First Wizarding War he authorizes the Aurors to use the Unforgivable Curses on suspects, and make no mistake, that means on suspects, people who have not been convicted of or even charged with crimes. He sends suspected criminals to prison without trial, and also cuts deals with convicted criminals behind the backs of the public. For more than ten years he imprisons his adult son in his own home, keeping under the Imperius Curse at all times and subjecting him to highly dehumanizing treatment. It can be argued that Crouch, Sr. is essentially the "good guys'" equivalent of Voldemort in his attitudes towards power and free will: namely, that he wants the former and has no respect for the latter.

Throughout the course of the novels, free will and volition are presented as highly important. Those who seek to preserve the free will of others and of themselves are seen as heroic; those who wish to take it away are villainous. It's not just Voldemort, but Dolores Umbridge as well who is opposed to free will, punishing students for voicing opinions that run contrary to her own and ultimately showing a willingness to use the Cruciatus Curse (on a minor and one of her students, no less!) in order to get information that she wants.

Now, out of all of these three curses, which do you think is the most insidious?

I would make a case for it being the Imperius Curse.

Another thing the three curses have in common is that none of them leave a physical mark on your body (Unless you count the whole "hair turning white" thing associated with Alice Longbottom). Get hit with Avada Kedavra? Leave behind a beautiful corpse. Get hit with Crucio? No need to worry about scars. Get hit with Imperio? Your unmarked body hides the mental scars.

However, for all that the curses leave no physical mark, the two that don't kill you definitely leave their psychological mark.

Torture is horrible. I'm not contesting that. It leaves horrible psychological scars, and in the case of real-world physical (and not just psychological) torture, can leave horrible physical scars as well. But Imperio isn't like Crucio or Avada Kedavra. Instead of hitting you over the head with the stick, it offers you the carrot. How does Harry describe it, when Crouch-as-Moody puts him under the Imperius Curse during class?

"It was the most wonderful feeling […] as every thought and worry in his head was wiped gently away, leaving nothing but a vague, untraceable happiness." –Goblet of Fire, 231.

The Imperius Curse not only magically coerces you into doing something that you would not do of your own free will, it makes you want to do it. It makes you happy to do these things. The caster tells you to torture your mother and you smile brightly at them and say, "Of course!" The Imperius Curse is not just mind control. It's brainwashing-lite. It's not enough that you're being coerced into doing something; you're being coerced into feeling happy about it.

And as for the long-term effects of the Imperius Curse, well, let's take a good look at Barty Crouch, Jr. Crouch, Jr. was subjected to the Imperius Curse full-time for more than ten years. He still possessed sufficient strength of will to throw it off when he saw his fellow Death Eaters at the Quidditch World Cup, but after ten years of mental domination on the part of his father, young Barty's sense of identity was so fractured and close to being extinguished that he was able to assume the identity of Alastor Moody, a person nearly totally unlike him, and be so convincing in his performance that he managed to trick everyone around him for several months. By the end of his life, young Barty does not have a sense of identity so much as he has roles that he assumes: Alastor Moody, hard-bitten Auror, and Barty Crouch, Jr., fanatical Death Eater. I'd be surprised if there was anything of his original personality left; Fudge barely needed that Dementor to Kiss him. The lights were still on, but nobody was home anymore.

If there is anything that Harry Potter wishes to teach us, it's that free will and consent are things to be guarded and protected, and that the stripping of volition is the hallmark of tyranny, no matter who's doing it or what side they claim to be fighting for. The one who claims to wish to impose their will upon you "for your own good" or "to create a better world" is not your friend. They're your enemy.

End Notes:

* I have no idea if the Unforgivable Curses are considered "Unforgivable" all across the Wizarding World, or if this is limited to Wizarding Britain. For the sake of this essay, I am going to presume that it's the former.

My interpretation of the character of Barty Crouch, Sr. is influenced heavily by a gigantic nine-part "dialogue" of sorts posted by Elkins in the years between the publishing of Goblet of Fire and Order of the Phoenix. It can be found at Overanalyzing the Text, under the banner of "C.R.A.B.C.U.S.T.A.R.D."