OK, but what about fictional characters? If the person we're mocking or humiliating doesn't even exist, we're safe, right?
"Because I want to make this bastard cry."
Nope, not even then. As hinted at above, people can still feel sympathetic toward fictional characters, treating them as stand-ins for some person or persons they know in real life. If you tell jokes about abusing children, for example, unless you take certain precautions, you're going to get some splashback.
What precautions? Well, as the joke writer, you "own" that fictional person, and there are several things about them you can tweak to make it permissible to mock them again.
"Like if I gave them a funny hat, or ...?"
Look for my column next week on children riding animals and throwing smaller children and animals at larger animals, in kind of a child/animal recreation of the Battle of Hoth.
So how did I get away with it? In those cases, I made the victims less sympathetic by sparing a lot of the details. The children and animals were described generally, with no names or specifics given. I didn't go into detail about the wounds they suffered or the bitterness of their tears. What few likable qualities children and animals possess weren't mentioned at all, and their various downsides were discussed heavily. All of this was done very deliberately, with the intent of forming a cartoonish image of a child or animal in the reader's mind, a caricature whom they wouldn't mind seeing get beaten up a little bit.
"Oh, so beating children is the answer?"
OK, but what if we tell a joke without a victim at all? That's super safe, right?
"Really though, what's the point if I can't humiliate someone?"
Nope, not even then. Because if you tell a joke or mention a topic that even implies the existence of a victim that your audience might feel sympathetic toward, you're going to be in trouble.
For example, did you ever consider how those girls from Nantucket actually feel about their poor upbringings?
Topics that vividly imply the existence of a victim are commonly called "triggers" after the way they trigger strong, unavoidable reactions in some people. Sexual assault is probably the most well-known trigger, well-known enough that no one should ever be tripping over it, except oh no, they do, all the time. Even mentioning rape is enough to make people who have suffered a sexual assault immediately relive the experience, and can make others visualize a rape victim whom they'll want to ferociously defend. And regardless of the intent of your joke or whatever not-totally-pro-rape statement you thought you were making, they will be furious at you for daring to find any humor in the subject at all.
"BUT I WAS BEING IRONIC!"
Other well-known triggers include suicide, and military post-traumatic stress disorder, and mental disabilities. You might think you used "retard" in an ironically retro fashion, just like you hilariously used to do in seventh grade, but a lot of people listening will have a friend or relative who's struggled with mental challenges, and they won't appreciate you using their condition as an insult. Life's rough enough on these people as is, without having to suffer the slings and arrows of morons.
"COMING UP WITH NEW INSULTS IS SUPER HARD, ALL RIGHT?"
And then there's the trickier question of whether these topics should be joked about at all, even among people who aren't triggered by them. If you and your three friends don't have any particularly close connections to the Holocaust, for example, and privately tell some jokes about it that don't offend anyone, does that do any harm? Not even pro-Holocaust jokes; some totally sympathetic gallows humor style joke. Or does speaking of the Holocaust (or rape, etc.) with anything other than sober reflection somehow diminish it in our minds and ruin our ability to properly consider (and speak about) its horrors? I don't know. Maybe?
"Wow ... wow. I don't know if it was that funny, Helen. Jesus."
Or are there healing, cathartic effects in telling such jokes? Supposed "cathartic effects" are often held up as a shield by terrible comedians defending their terrible jokes, but there is I suspect some merit to the principle in general. Still, I don't know. Maybe?
"IF IT STOPS YOU FROM THROWING ROCKS, I WAS TRYING TO BE CATHARTIC!"
However those tougher questions get settled, I think I gave you at least a few reasons not to make Holocaust and rape jokes up there (if you needed them). And given the endless variety of things that can be safely joked about, this shouldn't limit you too much. If you're stuck, maybe start ragging on people from Nantucket again? They've had it too easy for too long.
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