Fiji's Nationalist Vanua Tako Lavu Party has challenged the former coup convict, Major Josefa Savua, to help the police investigation into his brother and the former police commissioner, Col Isikia Savua.
The Nationalist president and another former coup convict, Iliesa Duvuloco, issued the challenge on Radio Legend.
It came just a day after the police special task force questioned Col Savua on his alleged role in masterminding the Speight coup and Commissioner Andrew Hughes said the file would most likely go to state prosecutors to determine whether charges should be laid.
Mr Duvuloco said Major Savua should go to Commissioner Hughes and "tell the truth about his role and his brother's role."
Mr Duvuloco says Major Savua "may have some good information that the police are wanting to get out the truth of the matter."
Mr Duvuloco's anger was spurred by statements at the recent Conservative Alliance party meeting where Major Savua said Nationalist prisoners on Nukulau had developed "evil spiritual beliefs" and cried all day.
During the coup, Major Savua marched his army engineering unit into parliament in support of Speight in full view of international television cameras.
Both he and Mr Duvuloco served their sentences on Nukulau with Speight and were released late last year.