A Court of Appeal hearing begins on Tuesday to determine whether David Tamihere's double murder conviction may have amounted to a miscarriage of justice.
Tamihere served 20-years in jail after being found guilty of murdering Swedish tourists Urban Hoglin and Heidi Paakkonen in Coromandel in 1989.
He was granted a rare Royal Prerogative of Mercy in 2020, after two key elements of the Crown case were proven wrong.
He's always maintained his innocence.
Tuesday's case will focus on the location of one victim's body - which was found more than 70 kilometres from the alleged murder scene - and evidence from a jailhouse informant who was later convicted of perjury.
Criminal barrister Nick Chisnall KC spoke to Corin Dann.