Dysart, who portrayed Leland MCKenzie in long-running legal drama L.A. Law, passed away at his home in Santa Monica, California on Sunday (05Apr15).

He was Emmy nominated as a supporting actor for his L.A. Law character for four straight years before winning in 1992.

He was the only actor to appear in every episode of the beloved show.

Dysart also played President Harry Truman in TV movie Day One and in the mini-series War and Remembrance in 1989, and returned to the 33rd U.S. leader's presidency six years later when he portrayed Secretary of War Henry L. Stimson in the TV movie Truman.

He also played a lot of doctors onscreen, most notably in The Hospital in 1971, opposite George C. Scott, 1979's Being There, The Terminal Man, The Thing and The Falcon & the Snowman.

He also portrayed J. Edgar Hoover twice - in the 1993 telefilm Marilyn & Bobby: Her Final Affair and in 1995's Panther.

His film and TV credits also included Pale Rider, Wall Street, Back to the Future III, Mask, Hard Rain, The People vs. Jean Harris, The Last Days of Patton, and Malice in Wonderland.

A private family memorial is being planned.