Maori Party co-leader Tariana Turia says outspoken MP Hone Harawira did not object when the party supported the National-led Government after the 2008 election.
On Monday, Mrs Turia broke her silence about Mr Harawira, who is the subject of an internal complaint after he criticised his party's support of National.
Mr Harawira is to attend a disciplinary meeting on Thursday over a newspaper article in which he said the party's caucus has betrayed its people by backing National's Marine and Coastal Area Bill.
Maori Party whip Te Ururoa Flavell made the complaint against the MP for Te Tai Tokerau.
Mrs Turia said all five Maori Party MPs agreed to support National and Mr Harawira voiced no objection in 2008.
Mr Harawira acknowledged on Monday that is true, but since the election a number of things have changed, including a widening of the inequality gap.
"The truth is that under National, the rich have got richer, the poor have gotten poorer, and the Maori people are very largely in the realm of the poor.
"All I'm saying is, we need to be speaking out about this, we need to be challenging these things, we need to be putting forward programmes that are going to change the nature of which governments deal with people in dire circumstance."
Mrs Turia says Mr Harawira's membership is up to the party to decide and there is a process it must go through.
Co-leader Pita Sharples says Mr Harawira still has a place within the party and the caucus is still a team.
Dr Sharples says the media has made a soap opera of the fact there are disagreements in some areas.
Mr Harawira says people in his Te Tai Tokerau electorate want him to stay with the party.
Listen to Hone Harawira