Double-murderer John Barlow has been denied a new appeal , despite forensic evidence used to convict him being called into doubt.
Governor-General Anand Satyanand, on advice from Justice Ministry and Justice Minister Annette King, refused Barlow's request to have his case heard a second time, the Dominion Post reported.
Barlow was found guilty at his third trial of the 1994 shootings of businessman Eugene Thomas and his son Gene in their central Wellington office. Jurors failed to reach verdicts in the first two trials.
At the third trial, the prosecution called a United States Federal Bureau of Investigation (FBI) ballistics expert who provided forensic evidence using lead content tests to match crime scene bullets with those in a box belonging to Barlow.
The FBI has since stopped its bullet-testing practice after scientific criticism it might produce a high rate of false matches of bullets.
It contacted law enforcement agencies worldwide, informing them of its decision.
Barlow's wife Angela Barlow told the newspaper she could not believe the verdict.
"They can't match the gun and they can't match the bullets," she said.
Barlow was denied a pardon in his first appeal in the Court of Appeal in October, 2006.
Having been denied the second appeal, the case will now head to the Privy Council where, Barlow's lawyer Greg King said he hoped to get a final ruling within a year.
Mr King said the Justice Ministry had ruled the FBI evidence was not key to Barlow's conviction.
"It seems pretty clear to me that it was critical. All we want is our day in court, and to be told we can't have that, well it's pretty disturbing."