A consummate actor with a gift for playing intelligent, occasionally reserved men in positions of authority, Christian Clemenson was an Emmy-winning performer whose work in features like “United 93” (2006) and television series like “Boston Legal” (ABC, 2004-08) made him among the busiest character actors in the 1990s and 2000s. He earned his training at Harvard and Yale before heading West to try his hand at screen acting; a lengthy career in supporting roles preceded his breakthrough with “Boston Legal,” on which his turn as the psychologically troubled lawyer Jerry “Hands” Esperson earned