Just thought about this:
What will happen if you cast a Vanishing Charm to a human? Will they to end up in "nothingness"? If that is true, then why was it not an unforgivable curse?
Just thought about this:
What will happen if you cast a Vanishing Charm to a human? Will they to end up in "nothingness"? If that is true, then why was it not an unforgivable curse?
Regarding "What will happen if you cast a Vanishing Charm to a human":
"Into non-being, which is to say, everything." (Minerva McGonagle, answering a riddle to enter Ravenclaw common room about "Where do Vanished objects go?".
This means that if you cast a simple Vanishing Charm on a human, they will permanently vanish - though her answer may imply that their matter may be distributed around if taken scientifically and not philosophically.
Note: Don't confuse Vanishing charm with Vanishing Cabinet which acted like a transporter and did NOT actually use the Vanishing charm despite sharing a name.
As far as it being a "an unforgivable curse", there are 2 reasons:
First, because the spell, as @beichst's answer noted, the spell isn't a pure attack spell. It has non-combat uses, and isn't even considered a Dark spell as it's being taught in Hogwarts.
Please note that MANY MANY spells can be used to kill someone (e.g. see Molly Weasley killing Bellatrix). You can't make EVERY spell that can be lethal if used in offensive way an "unforgivable".
In mortal world, if you're strong and skilled enough, you can kill someone with a pen or a rope just as well as with a gun or a knife. Same with Wizarding - a random person can't kill someone with Vanishing spell (or Avada for that matter)... and someone powerful and skilled can kill with A.K., with Vanishing, with tons of others (up to an including Wingardium Leviosa, a spell taught to grade 1).
Also, like any other legal system (especially a medieval one that Wizarding World uses), it's full of contradictions and arbitrary decisoins. Including in "unforgivable" designation.
Notice that there are TONS of spells used to mess with someone's mind (Legilimency, Lockhart's memory charms - the latter can be used to make people do your bidding) but only Imperio is an "unforgivable".
Then you have a non-lethal "Crucio" - despite the fact that you can use tons of OTHER spells to hurt and torture someone none of which is "unforgivable".
I would think it would be allowed because it has applications beyond using it just against people. All the unforgivable curses can really only be used against living things, in particular humans. Hence when used against people outside the context of teaching, and presumably in other restricted situations, they are a crime simply to be used. For example, during the Goblet of fire, we saw that Barty Crouch in the guise of Mad-Moody used the curses on arachnids as a teaching tool. It is the difference between firing a gun at a target range (legal) and firing a gun at a person (illegal) excepting when in might be legitimately used in self-defense.
By contrast, a Vanishing Spell would not be an Unforgivable crime simply to use as it has legitimate applications outside causing harm to another person. BTW, that doesn't mean it wouldn't be a crime to use it against another person. i.e. it probably would still be considered murder if not used in self-defense. But not simply using the spell.
Per the Wiki Harry Potter site:
Bold emphasis below is mine.
Unforgivable Curses are the three most powerful and sinister spells known to the wizarding world, and are tools of the Dark Arts. They were first classified as "Unforgivable" in 1717. They are the Killing Curse, Avada Kedavra, the Cruciatus Curse, Crucio, and the Imperius Curse, Imperio.
Using any of these three curses on another human being, Muggle or wizard, will result in a life sentence to Azkaban, unless there is sufficient evidence that the caster did so under the influence of the Imperius Curse. Aurors were permitted to use them during the First Wizarding War, while under Lord Voldemort's regime in 1997-1998, the curses were made legal,1 though this was presumably repealed following Voldemort's demise.
I have always thought that Molly used some sort of vanishing spell on Bellatrix. Especially looking at how they portrayed it in the films