Wellington - A New Zealander who served more than 12 years in prison for the murder of his parents and three siblings was found not guilty of the mass slaughter by a jury on Friday after his second trial.

David Bain, 37, was released in 2007 after the Privy Council in London - then New Zealand's highest court - ruled he had been the victim of "a substantial miscarriage of justice" when he was first tried in 1995 and sentenced to a minimum of 16 years in jail.

The council said the jury might have reached a different verdict had nine points of evidence raised by Bain's lawyers at his appeal in 2007 been presented to it.

The Court of Appeal had twice refused to change the verdict and the case went to the Privy Council after a prominent businessman and former rugby star, Joe Karam, organized a nationwide campaign and petition to have Bain freed.

The Privy Council did not declare him innocent and although the solicitor-general could have abandoned the case he decided that Bain, who was released on bail, should face another trial.

The jury returned its unanimous verdict in just under six hours following a 13-week trial at the Christchurch High Court which heard evidence from 184 witnesses.

Bain had again pleaded not guilty to shooting to death his father, Robin, 58, mother Margaret, 50, sisters Arawa, 19 and Laniet, 18, and brother Stephen, 14, at the family home in Dunedin on June 20, 1994.

Bain's defence throughout was that he was out on his morning newspaper delivery round when his father, who was having an incestuous affair with Laniet, killed the other family members before turning the gun on himself.

A message left on the family computer on the morning of the killings said, "I'm sorry, you are the only one who deserved to stay."

New Zealand's most well-known victim of injustice, Arthur Allan Thomas, who served nine years in prison for a double murder in 1970 he was later ruled not to have committed, was at the court to support Bain when the trial began. He told reporters he was there to see justice done.(dpa)