Coastal iwi in Bay of Plenty want a Royal Commission of Inquiry into the Rena disaster.
Te Moana A Toi iwi leaders group represents 16 iwi whose tribal waters and fisheries assets have been affected by tonnes of oil and debris spilled from the vessel that ran aground on a reef off Tauranga in October last year.
Chairman Charlie Tawhiao says it's important that as kaitiaki they know more about how the event unfolded.
He says many questions are being raised with iwi - such as why and how the disaster happened - which tribes cannot answer themselves.
Mr Tawhiao says they're looking to ensure the same sort of disaster doesn't happen again anywhere to any iwi, and an assurance that if any systems in dealing with a marine disaster are deficient, they will be addressed.
