Tau faces six charges of indecent assault on a female over 16, and three charges of attempting to pervert the course of justice.
69 year old Raniera (Sonny) Tau has pleaded not guilty to all charges. The trial in the Whangarei District Court before a jury is expected to last a week.
The indecent assault charges relate to alleged events between 1 January 2017 and 9 October 2019 committed at Rangi Point in Northland and Whangarei. The three remaining charges relate to allegations Tau offered the complainant money to drop the charges.
Tau was formerly chairman of Te Runanga-a-iwi o Ngapuhi, a collective of four organisations who represent the interests and aspirations of more than 125,000 people who identify themselves as Ngāpuhi. He stepped down from that role in 2019.