Onlookers have gasped in court as one of the men convicted of murdering bank teller Janine Balding was excluded from matching key DNA evidence.
It came as lawyers for convicted killer Stephen Wayne "Shorty" Jamieson insisted a complex legal challenge to cross-check DNA profiles could be resolved in minutes by NSW Police Commissioner Karen Webb.
Jamieson, 58, is serving a life sentence for leading a gang of five youths in the 1988 abduction, rape and murder of Janine Balding, condemned as barbaric by the sentencing judge.
Despite signing a confession, the convicted killer has long protested his innocence and pointed to a bandana used to gag Ms Balding as proof.
Results of DNA retesting of the bandana detailed in the NSW Supreme Court on Friday seemed to help Jamieson's case for an inquiry into his potential wrongful conviction.
"He is excluded," NSW Forensic and Analytical Science Service expert Clint Cochrane told the court.
People who appeared to be supporters of Jamieson audibly gasped and some raised their hands to their mouths after the comment.
Supporters of Ms Balding, including her brother David, were unmoved.
The partial profile of 11 genetic markers lifted from a part of the bandana did not match the full 21-marker profile of Jamieson, nor the three other males convicted alongside him, the court was told.
Assuming it was a single male, the partial DNA profile would match about one in five million individuals, Mr Cochrane said.
That left open the identity of the person or persons behind the DNA profile.
Mr Cochrane said he could not make a scientific determination about whether the partial profile was made up of multiple people, but there were no clear indications more than two were present.
Jamieson contended in his murder trial and ever since that he was a victim of mistaken identity.
He said he was confused with another "Shorty" and applied to the court to allow the other man's DNA profile to be tested against the bandana samples.
Queensland authorities have the profile from Mark "Shorty" Wells on file, but there is a dispute over the legality of NSW authorities using it for this purpose.
Mr Wells has denied any involvement in the rape or murder and has never been charged over the crime.
Jamieson's lawyer argued the court should order the DNA analysis be conducted.
"If (Wells's profile) can't be excluded, that becomes very powerful evidence in Mr Jamieson's contention that he was not the person and Mr Wells was," Richard Wilson SC said.
But the lawyers for NSW Attorney General Michael Daley said that course was not legally permissible.
Justice Ian Harrison suggested there could be ways around it.
"If someone were to put a note under my door saying we've done the test and he's excluded, it would save everyone including ... Ms Balding's relatives and Mr Jamieson - it would put all of this to rest at 1000 miles an hour," he said.
He more seriously then queried whether Commissioner Karen Webb could use her own powers to order an investigation.
The attorney-general's lawyer offered qualified agreement while Mr Wilson was more forthright.
"Every single male convicted has been excluded (from this profile)," he said.
"It's clearly within her power to investigate this lead.
"It would take an email and it would take two minutes."
NSW Police declined to comment while the matter was before the court.
Justice Harrison reserved his decision on the application until the new year.
No doubt has been raised about the convictions of the other three males involved in Ms Balding's abduction and murder, two of whom are serving life sentences without parole.
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