The Supreme Court today confirmed it would quash David Tamihere's double murder convictions after his trial was ruled 'unfair'.

He was found guilty in 1990 of killing Swedish tourists Urban Hoglin and Heidi Paakkonen, but the verdict was since overturned.

Private investigator Tim McKinnel says there's a 'clump of cases' from the mid-1980s to 2010 that are being evaluated through the system - and it points to a bigger problem.

"I think there are some structural issues we have in the justice system, like many similar countries where they have an adversarial system where two sides go to war and hope that the truth wins - and that's not always what happens." 

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