The father of slain Feilding farmer Scott Guy says it would be good if a private investigation into his son's death found new information, but he does not want to build up false hopes.
A passer-by found Scott Guy shot dead at the end of his driveway in the early hours of 8 July, 2010.
His brother-in-law Ewen Macdonald was found not guilty of the murder in July this year.
The Sensible Sentencing Trust is now helping to co-ordinate a team of private investigators working in partnership with the police.
Scott Guy's father, Bryan Guy, says his family still don't know who killed him, but they are focusing on building a future for their children and grandchildren.
He told Checkpoint the family is not dwelling on who may or may not have killed him.
"There's too many unanswered questions, so we don't dwell on it really."
Bryan Guy says he has not been approached by the investigators.
"If there is some other information out there that they can find, well that's great, because we might get some closure to things, but also we don't want to be building up false hopes either."
He says it was difficult to come to terms with revelations that Macdonald had vandalised the Guy's new home and set fire to an older house on their property.
Earlier this month, Macdonald was jailed for five years for six crimes committed before Scott Guy was killed.
They are: two charges of arson, vandalism of Scott and wife Kylee Guy's new home, poaching and killing two trophy stags, killing 19 calves and deliberate spilling of 16,000 litres of milk from a vat.