A lawyer for the families of the 29 men killed at Pike River say the Royal Commission is right to reopen the question of when they died.
The inquiry into mine disaster will investigate the timing and cause of death as it reviews the rescue and recovery effort.
In January the Chief Coroner ruled the men died during or immediately after the first explosion on 19 November, but possible new evidence has since emerged.
New images from the mine has been issued by the police since the inquest showing possible bodies and an open safety box.
Lawyer Colin Smith says this warrants investigation and demands answers from the Royal Commission.
He says that if the Royal Commission finds a different time of death from the Coroner, it will be up to the Coroner to reopen the inquest.