Moses was born in Los Angeles, the son of actress Marian McCargo (1932–2004) and advertising executive Richard Cantrell Moses Sr., who married in 1951 and divorced in 1963.
Marian remarried in 1970 to the Republican Congressman Alphonzo E. Bell Jr. (1914–2004). Congressman Bell adopted Moses and his brothers Rick and Harry. He briefly attended Wesleyan University.
Moses is probably best known for playing Cole Gioberti in the 1980s prime-time soap opera Falcon Crest, for six seasons from 1981–86 (although he returned for two guest appearances during the show's seventh season in 1987).

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