Tonga's leading pro-democracy MP Akilisi Pohiva has been granted bail and released from police custody after being arrested on Wednesday in connection with the November 16 riot.
The Chief Justice overturned a ruling by the Magistrates Court for Mr Pohiva to be further detained.
He's the second pro-democracy MP to be implicated in the riot which resulted in seven deaths and major damage to the capital's central business district.
His fellow people's Representative, Isileli Pulu, was arrested last week and has been charged with manslaughter, sedition and abetting wilful damage to property.
Our correspondent in Tonga, Mateni Tapueluelu, says Mr Pohiva is facing four charges of sedition.
"Mainly the government is trying to connect a political motive to the riot. And they're saying that it is implied by various speeches and statements that Akilisi said during the day that they planned the riot."
Mateni Tapueluelu says further arrests of pro-democracy movement figures are expected.
