The Supreme Court on Thursday ruled against former red-shirt leader Jatuporn Prompan, ordering him to serve prison terms in two defamation cases back-to-back.
Following the ruling, the Criminal Court sent a notice to Bangkok Remand Prison saying Jatuporn will need to serve another 11 months and 16 days over his 2009 defamation case filed against him by former prime minister Abhisit Vejjajiva.
The Supreme Court found Jatuporn guilty of defamation in December 2017 and sentenced him to 12 months in prison without suspension.
When the sentence was handed down, Jatuporn was already serving a sentence for defaming Mr Abhisit in a different case.
The lower court and the Appeal Court ordered a consecutive jail term, meaning he will start serving the new sentence after finishing the previous one.
However, Jatuporn appealed against the consecutive sentence order, saying it would deprive him of his rights and freedom.
The former red-shirt leader was released in August 2018 after completing the jail sentence for the first offence. The dispute over the consecutive sentence order was not yet finalised.
The Supreme Court ruled against him yesterday and ordered him to serve the remaining jail term.
Speaking before the ruling was made, Jatuporn, now the leader of the Thai Mai Thon group, said if he was ordered to serve the jail term, it would not affect the movement's campaign.
The group on Facebook said it will join a rally tomorrow organised by activist Sombat Boonngam-anong.