Herbert William Mullin is an American serial killer who killed thirteen people in California in the early 1970s. He confessed to the killings, which he claimed prevented earthquakes. In 1973, after a trial to determine whether he was insane or culpable, he was convicted of two murders in the first degree and nine in the second, and sentenced to life imprisonment. As of 2021, he has been denied parole eight times and is unlikely to ever be released.