Home People John Mahoney John Mahoney shows John Mahoney shows John Mahoney TV Shows (15) $#*! My Dad Says (2010) As Lt. Col. Wally Durham, He was 70 years old In Treatment (2008) As Walter Barnett, He was 67 years old Burn Notice (2007) He was 67 years old Foyle's War (2002) He was 62 years old Teacher's Pet (2000) He was 60 years old 3rd Rock from the Sun (1996) As Dr. Leonard Hamlin, He was 55 years old MADtv (1995) He was 55 years old ER (1994) He was 54 years old Frasier (1993) As Martin Crane, He was 53 years old The X-Files (1993) He was 53 years old The Human Factor (1992) As Dr. Alec McMurtry, He was 51 years old H.E.L.P. (1990) As Chief Patrick Meacham, He was 49 years old The Simpsons (1989) He was 49 years old Favorite Son (1988) As Lou Brenner, He was 48 years old Chicago Story (1982) He was 41 years old
