Powell died Sunday of natural causes at the California Medical Facility in Vacaville, according to the California Department of Corrections and Rehabilitation. He was serving a life sentence for kidnapping two LAPD officers and killing one, Officer Ian Campbell, in 1963.
Powell and Jimmy Lee Smith were pulled over by Campbell and Officer Karl Hettinger March 9, 1963, for making an illegal U turn. Powell and Smith kidnapped the officers and took them to an onion field in Bakersfield. There, Campbell was shot in the face and Hettinger managed to escape.
Smith and Powell were originally sentenced to death, but appeals and a retrial dragged out for over a decade. Their sentences were changed to life in prison when California's death penalty was deemed unconstitutional in 1972.
Smith was paroled in 1982. Powell was also set for release that year, but the decision was rescinded after an outpouring of opposition from the public, which included a 31,500-signature petition. Powell went on to be denied parole 11 times before his death.