National is calling for a broader investigation into whether the government's most senior ministers orchestrated a campaign against the Opposition over budget hacking claims.
The Treasury called in police after finding what it said was evidence of systematic attempts to hack budget secrets from its computer systems.
But police quickly concluded nothing illegal had happened and it later transpired National obtained details simply by searching the Treasury website.
The State Services Commission is investigating the Treasury's actions but cannot legally look at the role of government ministers in the aftermath.
RNZ political reporter Jo Moir has the story.
