Judge Heemi Maana Taumaunu was born in Gisborne, New Zealand, with tribal affiliations to Ngāti Pōrou (East Coast, North Island), and Ngāi Tahu (South Island), Judge Taumaunu completed primary and secondary school in Christchurch before joining the New Zealand Army as a Webb Class Regular Force Cadet in 1984. He then served as a Regular Force soldier in the Royal New Zealand Signals Corp for four years.
Graduating from Victoria University of Wellington in 1993 with a Bachelor of Laws, Judge Taumaunu practised as a barrister and solicitor in the Gisborne region for 10 years prior to his appointment as a District Court Judge in 2004. Judge Taumaunu is warranted to preside over jury, general and youth courts, is a resident Judge of the Auckland District Court, and regularly presides over Youth Courts in Waitākere, Gisborne, Ruatoria and Wairoa. Judge Taumaunu is the National Rangatahi Court Liaison Judge and the Chair of the District Court Kaupapa Māori Advisory Group. In June 2012, Judge Taumaunu was sworn in as a Judge of the Court Martial of New Zealand.
Judge Taumaunu was awarded the 2016 Veillard-Cybulski Foundation Award for his pioneering work in leading the development of the Rangatahi Courts of New Zealand.
Married with three children, Judge Taumaunu has a special interest in Youth Justice and, in particular, Youth Justice for recidivist Māori youth offenders. His Honour regularly presides over the Rangatahi Courts at Te Poho-o-Rawiri Marae in Gisborne, Hoani Waititi Marae in Waitākere, Ōrakei Marae in Auckland and Ngā Hau e Whā Marae in Christchurch.