Famous JFK Assassination Conspiracy Theorist Dies at 89 Mark Lane questioned the Warren Commission and coined 'grassy knoll' By Michael Harthorne, Newser Staff Posted May 13, 2016 2:03 PM CDT 44 comments Comments In this 1966 photo, lawyer Mark Lane points to a photo showing the route followed by the late President John F. Kennedy prior to his assassination. (AP Photo/Card) (Newser) – Mark Lane, "one of the most important experts on the Kennedy assassination," died Tuesday at his his home in Charlottesville, Virginia, at the age of 89, the New York Times reports. Lane came to national prominence with his best-selling 1966 book Rush to Judgment, which questioned the findings of the Warren Commission and concluded a second gunman helped Lee Harvey Oswald assassinate Kennedy. He was the first to use the now well-known phrase "grassy knoll." He went on to publish multiple books—and write a number of films—on the Kennedy assassination. “While I don’t agree with his conspiracy theories about President Kennedy’s assassination, he deserves credit for raising important questions,” the director of the University of Virginia's Center for Politics tells the Richmond Times-Dispatch. Lane was also a defense lawyer who represented some high-profile clients, including James Earl Ray and cult leader Jim Jones. Even after Ray was convicted of killing Martin Luther King Jr., Lane maintained his innocence and believed another conspiracy could be at play, the New York Daily News reports. Lane was also a civil-rights activist and served one term in the New York State Assembly. “His life was just an absolute testament to what people can become,” his assistant and friend Sue Herndon tells the Times-Dispatch. “He lived more lives than so many people.” Lane passed away one year before all government records of Kennedy's death are set to be made public.