Labour has turned down its former MP John Tamihere's bid to rejoin the party.
The one-time Cabinet minister and now Auckland mayoralty candidate had sent in his application along with a $100 donation late last year.
But the party's ruling council has turned him down and returned the money.
Mr Tamihere said he had not been given a good reason and told Morning Report Labour was trying to "gerrymander" the race for Auckland mayor.
Labour has already endorsed the incumbent, former Labour MP Phil Goff, in the contest.
"If your membership is not renewed, normally there has to be a very good reason for it. That reason's not been made available to me," Mr Tamihere said.
"For reasons unknown to me my reapplication for renewal has been declined.
"You're normally, under natural justice, given a right if someone's said negative things about you to at least have a say batting those things back. I haven't had that opportunity."
At the announcement of his mayoral candidacy last month, Mr Tamihere and running mate Christine Fletcher hit out at Mr Goff, saying he was a poor leader for both the council and the city.
Mr Tamihere said he had made it clear he was running for mayor as an independent so he did not even consider seeking support from Labour.
Senior member of the Labour Party's Māori council Rudy Taylor told Nine to Noon the party should have talked directly to Mr Tamihere before making its decision.
"The decision for the party is to determine which is the members that should be given a second chance and I thought he should be given a second chance. If you're talking about natural justice - bring the guy in so he can spell it out, what it is," Mr Taylor, from Te Kaunihera Māori, said.
Mr Taylor said the party could have set out conditions for Mr Tamihere's return to the party.
Labour Party president Nigel Haworth said as a matter of established practice we don't comment on individual cases that arise in our council's meetings.