The aunt of the Kahui twins who broke family ranks after the killings and said Chris Kahui was responsible has changed her mind.
Fiona King told the Weekend Herald police should reinvestigate the case and the role of her younger half-sister Macsyna King.
Fiona and sister Denise appeared on television in the weeks after the killings in 2006, furious at the behaviour of the so-called "tight 12".
They gave the name of a male member - Mr Kahui - as the killer, but it was bleeped out. They also gave his name to police.
The pair had been estranged from the family for several years at the time and were not involved with the tangi.
They became involved again after learning of the killings, attending a family meeting, where Macsyna told them Mr Kahui was responsible.
Fiona King told the Weekend Herald she did not blame Chris, but only passed on what she was told at the time.
She had since had doubts and was eventually called as one of his defence witnesses, saying Macsyna had also said the killer was "a woman following her around" then used the Maori word for ghost - "kehua".
The hatred between the older King sisters and Macsyna and her younger siblings was illustrated during the trial when a series of abusive texts between them was read out. But the oldest member of the family, Robert, yesterday said Fiona and Denise's disgust at the "tight 12" was rich given their treatment of Macsyna and the other younger siblings.
Chris Kahui's lawyers plan to make a formal complaint about the way police handled his twin sons' murder inquiry.
Mr Kahui's lawyer, Lorraine Smith, told the Weekend Herald yesterday she and her co- counsel, Michele Wilkinson Smith, would lodge a complaint with the Independent Police Complaints Authority (IPCA).
The IPCA is a judge that exists to investigate complaints of misconduct or neglect of duty by police officers.
Mr Kahui was found not guilty on Thursday after a six-week High Court trial where he was charged with murdering his 3-month-old sons Cru and Chris in June 2006.
The complaint will focus on information they say was not disclosed quickly enough to the defence team.
