The idea that you can harm somebody, by making an image of them (usually a wax doll), and sticking pins in it seems to be an old idea.
From what I understand, this practice comes from “voodoo”, as practiced by some in Haiti.
Is this true? Do Haitian voodoo practicioners actually set out to harm people by doing this?
Or is this mostly Hollywood and the domain of cheap fiction?
It’s Hollywood.
Voodoo is essentially spirit worship and as you might expect is a combination of yumyum from Catholicism and various African religions.
The pins-in-the-doll thing is evil sorcery intended to harm a person and is not limited to (or even widely practiced in) Haiti, and it’s not Voodoo. Power fetishes (power objects) used to house spirits of supernatural beings, including souls if you can get them, are used in some African religions practiced in the regions from which we drew our slave stock. Abuse of such devices with the intent to cause harm to others may happen alongside Voodoo, but the two traditions were conflated because they make good celluloid.
Well, it may be Hollywood that connects it to Afro-Caribbean religion, but as a magical practice it has a deep history in the Old World. Google books link to Witchcraft and Magic in Europe, Vol. 2 traces a parallel practice to the ancient Hittites.
As far as Voodoo goes, when you don’t know what kind of scary magic the Other possesses, best to project with your own culture’s dark magic.
ETA: Not disagreeing with anything Inigo Montoya said, just clarifying.
The Chinese have something similar too: wiki. Instead of dolls, you have something drawn on a piece of paper or some other object that symbolizes of the victim. And instead of pins, you have an old lady chanting and repeatedly beating the crap out of that object with a shoe.
YouTube video
Another YouTube video. I see that someone really doesn’t like Manchester United. 
Generally, the belief that like affects like, is called sympathetic magic and was/is a common pre-scientific way of thinking across human-kind.
It’s called symp…damn you westy!
Frazer’s Golden Bough is full of references to sympathetic magic. I remember reading it one month when I was sick in 5th grade [I was seriously bored, and saw it mentioned in another book and got my mom to get the unabridged version out of the library]
Fascinating. Found it on Project Gutenbergno idea if it is abridged or unabridged yet, need to reread it=)
True, but the use of a human-shaped figure to inflict harm on the human sympathetically tied to it is not universal. It does not seem to be a part of Haitian folk magic, for instance. It certainly is part of the folk magic traditions of the British Isles.
I read once, that the late President of Haiti (Francois Duvalier) hated President kennedy, and used Voodo to harm hime.
It wasn’t recorded whether Duvalier actually stuck pins into a doll, however.
It’s worth pinning down (so to speak) what you mean by Voodoo. Vodou, also spelled Vodoun or Voodoo, is the Afro-Caribbean religion of Haiti. It is a blend of French-style Catholicism, the traditional religions of West Africa (particularly what is now Benin and Nigeria and Angola / the Congos), as well as, probably, some of the Native American religious practices. As a religion, it’s much bigger than just magical practices: it includes ceremonies, relationships with divinities, and whole realms of the sacred. Historically, it has been stigmatized, seen as an inferior or degenerate version of Catholicism, and not something that upwardly mobile Haitians would necessarily admit to practicing.
So, did Papa Doc practice Voodoo? Yes, probably. Most Haitians do. But like any religion, Voodoo isn’t inherently a tool of harm. Millions of people practice Voodoo or allied religions without inflicting harm on anyone.
Is there a metaphycial structure within Voodoo by which one can harm another person? Yes, but it is considered both aberrant and very bad.
Did Papa Doc use such a mechanism? Quite possibly. He certainly used it in the sense of rumor-mill propaganda, but whether he believed in it and / or actually did anything is beyond my knowledge.
Did he use it against President Kennedy? Who knows? If he considered Kennedy an enemy, he might well have, but most practitioners of Voodoo would not harm even their enemies for the same reason Kennedy didn’t curse Papa Doc (or the Soviet leaders) within the framework of Catholicism.
Did any magical practices of Papa Doc cause Kennedy’s assassination? No. Even if you buy the logic on which magic operates, and even if you are a practitioner of and believer in Voodoo, such a specific cause-and-effect is so unlikely that it would have been easier just to hire a physical assassin and send him.
Papa Doc co-opted/bought off the Voudon establishment and used Voudon as a way to give his regime legitimacy.