The Waitangi Tribunal has accused the Crown of breaching the Treaty of Waitangi after partially opposing plans to leave the Rena on Astrolabe Reef without having consulted affected Maori.

In a report released today, it states that two Bay of Plenty claims concerning the removal of the ship's wreck from the reef were well-founded.

Containers fall from the Rena ship back in 2011.

The claims submitted by the Motiti Rohe Moana Trust, the Ngai Te Hapu Incorporated Society and the Mataatua District Maori Council were heard under urgency in Tauranga in June and July 2014 by a Tribunal panel comprising Judge Sarah Reeves, Ron Crosby, Sir Douglas Kidd and Professor Sir Tamati Reedy.

The Crown's deal to take $10.4 million if it backed the Rena's owner's wish to leave it on Astrolabe Reef breached the Treaty of Waitangi, though it redeemed itself by partially opposing the plan in the end, reads the report.

The Tribunal concludes that the Crown signed the deed without having sufficient knowledge of Maori interests in the reef and without having consulted affected Maori, despite it having been both practical and important for the Crown to have done so.

The Crown's conduct, the tribunal found, breached the Treaty principle of partnership and mutual benefit.

The final decision follows the interim report issued in July ahead of the Cabinet's decision in August on whether to support the owner' application for resource consent to leave the wreck on the reef.

In 2012 the Government, Daina Shipping and the Swedish Club signed a $27.1 million settlement for costs inflicted from the ship's grounding in October 2011.

A further $10.4million was promised to the government should the owners be permitted to leave the remainder of the wreck on Astrolabe Reef

The Tribunal's final report focuses on the Crown's conduct in entering into the Wreck Removal Deed as part of its October 2012 settlement with the Rena owners.

The deed obliged the Crown to consider, in good faith, supporting an application by the owners for resource consent.

These obligations, the tribunal found, placed the Rena owners in a special position in the resource consent process in a way that could significantly affect Maori interests in Otaiti (Astrolabe) Reef.

The tribunal considered that, by opting in August 2014 to partially oppose the Rena owners' resource consent application, the Crown had averted the primary prejudice that could have arisen.

But the Tribunal also found the Crown's conduct had damaged its treaty partnership with the claimants and put at risk their ability to engage meaningfully in the resource consent process.

The Tribunal recommended that the Crown take active steps to protect Maori interests in the resource consent process and assist the active participation of affected Maori.