Biography: Herbert William Mullin (April 18, 1947 – August 18, 2022) was an American serial killer who killed 13 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 legally insane or culpable, he was convicted of two murders in the first-degree and nine in the second-degree and sentenced to life imprisonment. During his imprisonment, he was denied parole eight times.