A Waitangi Tribunal member has stepped down after Crown lawyers queried his right to hear the Ngapuhi mandate claim.
Tim Castle was on the panel that agreed to hear the grievance of many hapu about Tuhoronuku, the board claiming the mandate to settle Ngapuhi claims.
But his warrant expired last month and the Crown said the law did not appear to allow him to remain on the tribunal for the substantive hearing next month.
Lawyers for the claimants told the tribunal Mr Castle was a very effective panel member who should remain.
Maori affairs Minister Te Ururoa Flavell said last week he saw no reason why Mr Castle should not continue.
But the tribunal said Mr Castle felt that continued debate and uncertainty about his position would be a distraction from the urgent hearing.