Randall Darius Jackson (born June 23, 1956) is an American record executive, television presenter and musician, best known as a judge on American Idol from 2002 to 2013. Jackson began his career in the 1980s as a session musician playing bass guitar for an array of jazz, pop, rock, and R&B performers. He moved on to work in music production and in the A&R department at Columbia Records and MCA Records. Jackson is best known from his appearances as the longest-serving judge on American Idol and executive producer for MTV's America's Best Dance…