The Māori Council has dropped lawyer Donna Hall from any further work on the Trans-Pacific Partnership claim.
The council is one of the Māori claimants seeking an urgent Waitangi Tribunal hearing on the agreement because they claim it breaches the Treaty.
Documents leaked to Te Manu Korihi suggest council members were concerned about a potential conflict of interest, since Ms Hall is married to council chair Tā Edward Taihakurei Durie.
Co-chair Maanu Paul would not elaborate on the reasons, but said Donna Hall's firm Woodward Law remained the Māori Council's legal advisor on other matters, just not the TPP.
Te Manu Korihi understands from other council sources that Sir Eddie Durie refused to co-sign a letter from the Māori Council to the government, denouncing the trade deal.
Ms Hall said it was not uncommon for Mr Paul to sack lawyers - and she would respond in due course.