An independent investigation into the past conduct of National Party MP Sam Uffindell could come up empty handed.
Otago University law professor Andrew Geddis says Maria Dew, a Queen's Counsel, has been appointed to provide legitimacy to the investigation, but she has no ability to force potential witnesses to speak to the inquiry.
He says the investigation will rely on people being willing to come forward.
Geddis spoke to Guyon Espiner.
