The father of Scott Watson says the internal investigation into complaints he made against the Deputy Police Commissioner Rob Pope was too narrow.
Watson is serving a life sentence for the murders of Ben Smart and Olivia Hope in the Marlborough Sounds 10 years ago.
His father Chris Watson had complained Mr Pope made false statements in a sworn affidavit presented to the Wellington High Court in February 1998, in order to advance the case against his son.
However a police investigation has found the then-Detective Inspector Pope did not mislead the court and the allegation of swearing a false affidavit was not substantiated.
Mr Watson says his complaint was handled in a literal fashion. He hopes an investigation by the Independent Police Conduct Authority will be broader.