"psychopath test": real or bogus?

I recently ran across this test (it’s all over the web) that’s supposed to show if you think like a psychopath. I’ve been having fun amusing my friends with it, but now I’d like to know if it’s real or bogus, or maybe an “urban legend.”

The test is supposed to be based on a real test forensic psychiatrists use. You tell the person you are testing this story: “A girl went to her mother’s funeral, and she met this man she really liked. Only thing was, she forgot to get his phone number before he left. A week later, the girl killed her sister. Why?” Most people will answer “I don’t know” or maybe “uh, the girl found out her sister was dating the guy?” or something like that. But if they answer “she hoped the guy would show up at her sister’s funeral and she could get his phone number,” then you are advised that person thinks like a psychopath and you should stay away from him/her.

The description of the test usually says it’s been used with serial killers, who inevitably give the psychopathic answer. It also usually says the test was designed by a “famous American psychiatrist” but the psychiatrist’s name is never given.

What do the teeming masses think? Is this test thing real, or a hoax? If it’s real, who’s the famous psychiatrist who designed it?

Been there, done that: Psychopath Test