The rifle used to kill five members of the Bain family is being returned to David Bain's advocate Joe Karam, 23 years after the infamous murders.
Around 200 exhibits from the long-running case are being disposed of by the Crown, Fairfax reports.
David Bain was convicted of murdering his parents and three siblings in Dunedin in June 1994, and served 13 years in prison before the Privy Council quashed his convictions.
He was subsequently found not guilty on all charges at a retrial in 2009.
Bain's defence argued his father Robin had murdered his wife and three of his children before turning the gun on himself.
Among the exhibits being returned are the .22 semi-automatic rifle, magazines, ammunition and trigger lock used in the murders, along with bloodied white gloves which were allegedly used by the killer.
Bain - who changed his name this year to William David Cullen Davies - owned the Winchester rifle, which he kept in his wardrobe. But as he no longer has a firearms licence, the rifle will be returned to his long-time advocate, former All Black Joe Karam.
Bain's T-shirt, socks, underwear, running shoes, and other clothes will also be returned to him, Fairfax reports.
Fairfax reported Robin Bain's brother Michael said Crown Law had told him it had received a written declaration that David Bain had transferred his property interest in the items to Karam.
Crown Law had consulted the Bains' extended family, who had indicated they would object to any critical evidence from the trial being returned to David Bain.
The Herald is seeking comment from Michael Bain and Joe Karam.
Michael Bain was quoted by Fairfax saying he and the rest of the family would be "incredulous if the police were contemplating handing over the rifle or ammunition or fire arms licence to David, as he had not yet been able to prove his innocence in the matter".
Karam told Fairfax he had nothing to say about the return of the rifle or other exhibits, and that the information was legally confidential.