Note: I got badly taken in by this one... it turns out the Nature article by Peter Watts is, erm, science fiction. That's right, it didn't happen. Thanks to PZ for correcting me. (See more).
In an absolutely mind-boggling case reported by Nature, a skeptic by the name Linus C. Velikovsky (no, not that Velikovsky) was charged with the negligible homicide of one Lacey Hillcrest. The story runs as follows: five years ago, Hillcrest was diagnosed with terminal lymphatic cancer and given 6 months to live, but (so the story runs) she survived miraculously due to the placebo effect activated by a necklace supposedly containing a fragment of the cross of Jesus. Then, in June of this year, she visited Velikovsky's Museum of Quackery and Pseudoscience where she saw a display on the placebo effect, immediately rendering her "subdued and uncommunicative" and she died less than a month later. This was enough to get Velikovsky charged - the "vile little Russian" (in Hillcrest's sister's words) was responsible for her death. Luckily, the jury wasn't absolutely crazy and it returned a verdict of not guilty.
A couple of comments. Firstly, the placebo effect is much misunderstood, in fact, the idea that it involves "mind over matter" is simply a myth. There is no evidence whatsoever that one's mood or beliefs can influence the objective course of a disease, only that placebos may help patients cope better with subjective aspects of a disease (like pain). Indeed, a large, well-constructed study published last year in the journal Cancer concluded that "The current results add to the weight of the evidence that emotional functioning is not an independent predictor of survival in cancer patients" (emphasis added). In other words, there is no evidence that the placebo effect can alter the course of a disease like cancer. On this evidence alone Velikovsky is innocent: he simply cannot be guilty of killing Hillcrest because her necklace and the placebo effect weren't responsible for her survival.
Secondly, this case beautifully demonstrates the dangers of non-scientific and illogical thinking. The prosecutors and Hillcrest's family committed the logical fallacy of post hoc ergo propter hoc: she died soon after seeing Velikovsky's exhibit, therefore she must have died as a result of seeing it. While I can understand the emotional cachet of this view for her family, I fail completely to understand why the prosecutors fell for it - one would expect lawyers to be familiar with an elementary logical error like confusing correlation with causation. I've long thought all high school students should be required to learn elementary logic and critical thinking, and this case demonstrates just how necessary that is.
Third and finally, this case also shows just how far the skeptical movement has to go before it gains mainstream acceptance. While it seems Velikovsky didn't help his cause by being impolite and unnecessarily combative, there was never even a semblance of a case against him, he was guilty of nothing more than being a grumpy skeptic. I'm afraid that until we get the public to understand the value of skepticism, until we've made skepticism more mainstream, this sort of low-level persecution (in less extreme forms) will continue.
Anyway, at least Velikovsky wasn't found guilty, now that would have been a travesty.
(See also: Steven Novella's blog entries on the placebo effect, here, here, and here).