Whether they're mining for viewers, wanted a fresh opinion or needed a back-up plan in case of Paula Abdul's inevitable meltdown, American Idol will welcome a fourth judge to the program this year, executive producer Simon Fuller said. Grammy-winning songwriter Kara DioGuardi will sit at the judges' table as the show goes into its eighth season amidst slumping ratings. DioGuardi is no stranger to the show, having already penned songs for Kelly Clarkson, Taylor Hicks and Katherine McPhee. Additionally, DioGuardi has written major hits for Christina Aguliera ("Ain't No Other Man"), Hilary Duff ("Come Clean") and Ashlee Simpson ("Pieces of Me"). On the downside, DioGuardi also worked on albums by Lindsay Lohan, Kelly Osbourne and Paris Hilton. Idol's decision to go with four judges fulltime was partly inspired by the fact that the format had worked well on international Idol programs.