Lord St Davids was formerly a member of the House of Lords, and served as a Deputy Speaker from 1995. As an hereditary peer, he was excluded from the House by the House of Lords Act 1999.
He married Augusta Victoria Correa Larrain in 1965. They have two children:
He is also a co-heir to the barony of Grey de Ruthyn (1324) holding a share of the abeyant title.
Lord St Davids was a partner in the London stockbroking firm of Scrimgeour Kemp-Gee, later absorbed by Citicorp. He has a keen interest in music, specialising in Rossini, and has contributed to "Music & Letters".