Tongan academic Dr Sitiveni Halapua, says the rioters' anger was fostered by the Government producing its own ideas on political reform.
Dr Halapua, from Hawaii's East West Centre, was the vice chairman of the parliamentary National Committee on Political Reform.
He took over as chair after Prince Tu'ipelehake died in a car crash in California earlier this year.
Dr Halapua says the government had been encouraging those agitating for reform to wait until the report was presented which happened in early October.
"And the people were waiting and when the report was submitted, and just before it was completed, the presentation, discussion and answering questions from the members of the House, the government came up with its alternative road map and that is what triggered everything."