Matthew Michael Carnahan (sometimes identified as Matt Carnahan) is an American screenwriter who wrote the feature film The Kingdom (2007), and the film adaptation of the hit BBC television drama serial State of Play. Carnahan also wrote the screenplay for Lions for Lambs for United Artists. His brother is Joe Carnahan, who wrote and directed Narc (2002), Smokin' Aces (2006) and The A-Team (2010).