[1][2][3][4] His maternal grandfather was Arthur Edwards Manning[3] who served as mayor of Hamilton from 1912 to 1915, and his paternal great-aunt was the artist Helen Crabb.
[5] He was educated at Southwell School in Hamilton from 1939 to 1942, and King's College, Auckland from 1943 to 1946.
[1] In 1956, Tompkins married Erica Lya Felicity Faris, and the couple had three children, including Arthur Tompkins, who was appointed a district court judge in 1997.
[1] Tompkins was president of the Hamilton District Law Society between 1969 and 1971, and active in the New Zealand Law Society, serving as a council member from 1969 to 1971 and vice president from 1979 to 1981.
[1] In the 1999 Queen's Birthday Honours, he was appointed a Knight Companion of the New Zealand Order of Merit, for services as a judge of the High Court and to the community.