Justin from Dog the Bounty Hunter was a character who served as part of Chapman's team during the first season of the show. He left the show after he got into a car accident in Hawaii. He was the nephew of Duane 'Dog' Chapman.
1 Additional Answer
Justin Bihang who was on the dog, crashed his Aunt Beth's vehicle and burnt a hole in the dashboard. This incident led to a near fight with Beth and he now has a less active role.