Had wanted to be a real police officer and attended the L.A. Police Academy.

Attended Juilliard at the same time that Homicide: Life on the Street (1993) co-star Andre Braugher attended. He was a freshman when Braugher was a senior. Braugher played Iago in a performance of "Othello," and Diamond played one of his servants.

Plays guitar in the rock band "Chuck Valiant". His wife, Marnie McPhail is the lead singer.

His mother Allison is an astrologer and lives in Malvern, Pennsylvania.

Attended Trinity School, NYC

The family summered in Ocean City, New Jersey, and lived there for a year when Reed was 7.

His father, Bob Diamond, directed The Joe Franklin Show (1950), and later was director of supernumeraries and children with the Metropolitan Opera in New York City.

Ex-son-in-law of Stephen F. Kesten.

Series regular in Designated Survivor (2016) and his costar, Brian Howe from Journeyman (2007) was a guest star in 2017.