A 48-year-old man was jailed for 30 years on Friday for insulting the monarchy on Facebook, in one of the toughest-known sentences passed under the lese majeste law.
Under Section 112 of the Criminal Code, 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 Sriboonpeng 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 AFP.
"It's broken the record," she said about the severe jail term, adding that because Pongsak was arrested while Thailand was still under martial law there was no right to appeal the sentence passed by the military court.
Authorities rarely provide details of cases, leaving rights groups to follow prosecutions across the country.
According to iLaw, a local rights group that monitors such cases, there were just two ongoing prosecutions for royal defamation before the coup. Now that number is at least 56.
Critics of the law say it has been used as a weapon against political enemies of the royalist elite and their military allies and now targets those opposed to the 2014 coup.
In another conviction this week, a military court in in Chiang Rai sentenced a man with a history of mental illness to five years in jail for lese majeste.
Samak Pantay, 48, was found guilty on Thursday of slashing a portrait of the King and Queen in July last year, lawyer Anon Numpa said.
"He confessed to the charge so the judge commuted the sentence to five years," he said, adding that Samak has been medically certified as mentally sick for "more than 10 years".
In April a businessman was jailed for 25 years for posting Facebook messages deemed to be defamatory to the monarchy in a ruling rights groups described as one of the harshest known.