In 1987 he initiated a successful appeal against the State-Owned Enterprises Act leading to actions against the Crown relating to land, forests, fisheries and te reo Māori (mortgaging his farm at Taipuha for the expenses).
His mother, Lillian, was Irish-Scottish and his father, Graham, of mixed Anglo-Saxon and Māori ancestry; he was their third son.
As well as being a Pākehā–Māori marriage, the bride was Catholic and the groom Anglican, so the couple married in the local police station.
He retrieved tūpuna Māori from an English auction house in 1988, and stopped the public sale of human remains.
Latimer was active in other organisations, the Anglican General Synod, on the board of the Museum of New Zealand Te Papa Tongarewa, a member of the Alcoholic Liquor Advisory Council and was a director of several commercial enterprises.