A running joke of the Wizarding World of Harry Potter is that it's not safe. It may be a tired complaint, but one that's perfectly justified. On top of the usual bloodthirsty creature or death trap, this magical setting has no shortage of dangerous spells and potions. Many of them are not only readily available but also in close proximity to children. In short, J.K. Rowling's beloved creation is a lawsuit waiting to happen.
True, it has certain incantations and devices that are frowned on. Namely, the three Unforgivable Curses will instantly result in a prison sentence. That said, the wizard realm comes with other questionable spells and potions. Crossing all sorts of moral and ethical bounds, they should be held in the same low regard.
7 Love Potion
Considering the plethora of potions in the Wizarding World, it's ironic that one of the most unsettling is among the most clichéd. As the name suggests, love potions make the drinker infatuated with a specific person. He/she is blindly obsessed and subject to the brewers' whims, willing to do anything to please them. That sounds eerily similar to the Imperius Curse.
After all, it's just as effective at influencing one's behavior. The potion takes away any agency a person normally has. At least the Imperius goes all the way and eliminates any mental faculties. With the love potion, you still believe your mind is your own. Simply put, you could give consent, but not informed consent. Fans are lucky they never see such a scenario go further, especially with hormonal teenagers!
6 Vera Verto
This is one of the weirder spells in a wizard's repertoire. Vera Verto turns animals into goblets. The students test it on their pets, but it could theoretically work on any creature. Why they'd ever want to do that is a mystery in itself. Humans are technically animals, so would it work on them? Well, that's not the point.
The problem is that this spell borders on animal abuse. It changes creatures' entire body structure, and they don't know why. What's more, is that they still seem to be sentient; they're just unable to move as a person drinks from them. That's got to be such a weird and demeaning sensation that it scars them for life. PETA would have a field day with such a spell.
5 Diffindo
Known as the Severing Charm, Diffindo cuts objects like a knife. It's curiously absent from the films, but it pops up plenty of times elsewhere. Harry uses it throughout the books and several of the games to slice fabric and other material. However, why stop there?
Diffindo seems to have no limit to what it can sever. A sadistic wizard might turn the spell toward the flesh. What's to stop a maniac from slitting a throat or worse? People don't handle sharp objects without proper precautions; sharp spells should have similar limits.
4 Sectumsempra
This spell is not in the standard curriculum, and it's easy to see why. Harry learns it from the Half-Blood Prince's book and subsequently uses it on Draco Malfoy. This not only puts him down for the count, but it inflicts several bloody wounds which leave him clinging for life. Had Snape not intervened, Malfoy would have bled out.
Harry is rightfully appalled at his handiwork. One could see Sectumsempra as an alternative to the Killing Curse, yet arguably worse. After all, it creates a slower, more painful, and downright savage demise. If Avada Kadavra is a bullet to the head, then Sectumsempra is death by a thousand cuts. Thus, virtuous wizards should hold it in even greater contempt.
3 Polyjuice Potion
This particular potion can turn the drinker into anyone. Granted, it's incredibly complicated as far as brewing and ingredients. The mixture even calls for hair from the target and a month of preparation. That said, it's still doable for a school kid, especially a star student like Hermione.
This might be excusable if the Wizarding World had safeguards against such impersonations, but that's not the case. In fact, the characters use Polyjuice Potion to infiltrate secure facilities like the Ministry of Magic and Gringotts Bank. It would theoretically work on other government installations as well. In essence, no place is safe from this shape-shifting substance. Polyjuice Potion takes identity theft to a whole new level.
2 Obliviate
For those wondering how the fraudulent Gilderoy Lockart has a career, look no further than this despicable trick. He uses Obliviate to erase the memories of great wizards and then takes credit for their achievements. This is equal parts scummy and twisted. The Memory Charm robs people of their sense of self. They have no idea who they are or what they've done. Any life experiences are erased. Worst of all, it has no quick fix: Lockart spends years recovering after it backfires on him. Any spell that leaves one hospitalized for that long is obviously harmful.
More dubious, however, are the ethical ramifications. On top of wiping an individual's memories, Obliviate can also erase all knowledge of a person from their peers' minds. Hermione uses it on her parents to prevent them from becoming collateral damage, but more nefarious wizards would wield it to un-person an individual and forever cast him/her out of society. One shudders to think how that would play into the modern age of cancel culture. People shouldn't be able to sever all human connections with a flick of the wrist.
1 Living Death
Professor Slughorn tasks students with brewing this potion to earn a prize of Liquid Luck. The vial of good fortune is sketchy enough, but the subject of the lesson is far worse. It's hard to imagine anything good coming from a substance called "Living Death." While its purpose is unclear, the resulting liquid dissolves a leaf in a few seconds. Slughorn says that one drop of this liquid would kill them all, so why is it anywhere near children?
The world already has a strong stigma surrounding chemical weapons, but this is deadlier than any of them. It doesn't take a genius to figure out how sinister wizards could abuse it. Even spilling a batch of Living Death would lead to one's demise, and kids are prone to such stupid mistakes. At the very least, it shouldn't be in a classroom. The equivalent would be fashioning flesh-eating acid in a high school chemistry course.