The actor William Marshall would have been a
great black guest Columbo villain in the 1970's. He is tall, good looking and played the haughty genius
Dr Richard Daystrom in the classic Star
Trek episode "The Ultimate Computer".
Yes, Marshall would have been perfect as a Columbo murderer. As Daystrom he was obsessive, brilliant, arrogant and often condescending, with a imposing voice and physical presence. Great idea, YM!