United Future Leader Peter Dunne hopes a new investigation will reveal whether his email records mistakenly sent to the Henry GCSB inquiry and temporarily accessible throughout the parliamentary complex were read by anyone not authorised to see them.
Mr Dunne resigned after refusing to release the full content of his emails to Fairfax reporter Andrea Vance in the days before her article revealing key points of the GCSB report including potentially illegal spying on New Zealanders by the agency.
A file containing the full emails between him and Ms Vance was mistakenly provided to the Henry Inquiry on May 21 but returned 45 minutes later. Inquiry boss David Henry has said the file was never opened.
However Mr Dunne also said the file had been on the Parliamentary Service server for five hours earlier that day.
"It is not clear whether the file was accessed during that time, and if so by whom."
Mr Dunne had written to Parliament's Speaker of the House, David Carter, seeking his assurance that the emails were not accessed during that time.
A week after the emails were posted on the parliamentary server - which Mr Dunne believes means they were accessible to others within the complex - NZ First Leader Winston Peters claimed Mr Dunne was responsible for the GCSB leak.
Mr Peters subsequently said his claim was based on his knowledge of the emails between Mr Dunne and Ms Vance but yesterday he refused to confirm whether or not he had accessed the file.
Mr Dunne told reporters Mr Carter had advised him Parliamentary Service was now doing more detailed work to determine whether they were accessed, and if so by whom.
However, he didn't believe Mr Peters' claim he'd seen the emails.
"I've challenged him before to put up or shut up, and every time it's fallen on deaf ears ... I suspect it's all bluff."
However Prime Minister John Key had little sympathy for him, saying yesterday that no minister, including Mr Dunne, complained about the inquiry's terms of reference.
The inquiry list grows
• The Kitteridge Inquiry into the GCSB's compliance with relevant law
• The Henry Inquiry into the leak of the Kitteridge report
• Privileges Committee hearings into the conduct of the Henry Inquiry
• Speaker David Carter's inquiry into whether Peter Dunne's emails were subject to unauthorised access