Justin started his career at the age of 11, because he had a crush on a girl. Only three years later he got a role in The Dead Pool starring Clint Eastwood. From that point on he mostly starred in TV productions. In 1994, he hit big with the role of Jimmy Olsen in Lois And Clark, a part Michael Landes had before him. Justin was on the show from the 2nd to the 4th (and last) season, when the show ended.
After the end of Lois And Clark, Justin has gotten more movie roles, but he has also done a couple of TV productions as well.
One of Justin's most controversial movies is Child's Play 3, as it was blamed by the media for causing two young boys to murder a two-year-old in England. Although there was absolutely no evidence to suggest that either boy had ever seen that particular film.