A High Court judge says police and ESR must respond to questions of whether they may have breached court orders in the case of a murderer and rapist.
Teina Pora was convicted in 1994 of the rape and murder of Susan Burdett.
Pora's legal team argues that the conviction was based on a false confession and has asked for a Royal Prerogative of Mercy.
At the High Court in Auckland in June, lawyer Jonathan Krebs said Pora had encountered delays in getting hold of some material he requested from police and ESR, a Crown Research Institute.
Mr Krebs questions whether police had the evidence tested without telling Pora's legal team.
Court orders made in 2012 require that police and ESR to consult with Pora's lawyers before doing any testing.
Justice Heath has directed both to respond to Mr Krebs' concerns.