It is one of the toughest known sentences passed under the junta ruled kingdom’s draconian lese majesty law.
Thai King Bhumibol Adulyadej, 87, is protected by one of the world’s strictest royal defamation rules under which anyone convicted of insulting the king, queen, heir or regent faces up to 15 years in prison on each count.
On Friday Bangkok’s Military Court found Pongsak guilty of posting messages and pictures defaming the monarchy in six posts on the social networking website.
He was sentenced to 10 years on each count with the 60-year jail term halved after he pleaded guilty, his lawyer Sasinan Thamnithinan told.
“It’s broken the record,” she said of the severe jail term.
Since the Thai military seized power in a couple of last year, the number of prosecutions for royal defamation has risen from two to 56.
In April a 58 year old businessman was jailed for 25 years for posting Facebook messages deemed to be defamatory to the monarchy.
Thailand’s ruling military replaced martial law with new powers in April retaining much of the same authority but under the new orders civilians can now appeal to a higher tribunal for lese majesty crimes, though they are still tried at a military court.