Johnny Knoxville, Writer: Jackass: The Movie. Johnny Knoxville was born on March 11, 1971 in Knoxville, Tennessee, USA as Philip John Clapp. He is a writer and producer, known for Jackass: The Movie (2002), Jackass Number Two (2006) and Jackass Presents: Bad Grandpa (2013). He has been married to Naomi Nelson since September 24, 2010. They have two children. He was previously married to Melanie Lynn Cates.