The Police Commissioner is considering whether to reopen the investigation of the Crewe murders in 1970, following a plea from the couple's daughter.
The bodies of Harvey and Jeanette Crewe were dumped in the Waikato River 40 years ago and their 18-month-old daughter Rochelle was found in her cot in the family's farmhouse. The killer has never been found.
Now aged 41, Rochelle, whose current identity is not publicly known, has written to Police Commissioner Howard Broad asking him to reopen the case so that she can find out who killed her parents.
Mr Broad says that he will look at her request but that it may be a very long shot to expect any other court action to flow from this.
He says there are a lot of questions, and contested issues, and while he's not sure whether it's possible to find answers, he will certainly be considering the letter.
Arthur Allan Thomas was twice convicted of murdering the couple but was pardoned in 1979.
Non-prosecution of officers questioned
The New Zealand Herald has a statement from Rochelle saying she wants to know why police officers implicated in the planting of evidence to frame Mr Thomas were never prosecuted.
Mr Broad says the decision not to prosecute two detectives was based on independent legal advice and is unlikely to change unless there is something like new evidence.
The barrister who represented Mr Thomas at the 1980 Royal Commission into the case, Peter Williams, is conducting his own review and says he supports Rochelle's desire to have the truth come out.
Mr Williams says he is looking at the possible involvement of Jeanette Crewe's father, Len Demler, in the couple's murder.