(Bloomberg) -- A Thai court on Tuesday sentenced a pro-democracy activist, who spearheaded an unprecedented movement calling for monarchy reform, to four years in prison on charges of breaking the country’s royal insult law.

Human rights lawyer Arnon Nampa was found guilty of violating article 112 of Thailand’s penal code known as lese majeste that carries a punishment of up to 15 years in prison for each instance of defaming, insulting or threatening the king, queen, heir apparent or regent. The court said Arnon broke the law by making a speech calling for monarchy reform on Oct. 14, 2020 at a protest rally in the Thai capital, his lawyer Krisadang Nutcharus said.

Arnon was also found guilty of breaching the emergency rules imposed in the wake of the Covid outbreak but was acquitted of seven other charges, Krisadang said. He was also fined 20,000 baht ($550).

Read More: How Thai Law on Royal Insults Caused Political Crisis: QuickTake   

The activist  denies any wrongdoing. Arnon was remanded to the Bangkok remand prison as the trial court referred his appeal for bail to the court of appeals, which is likely to take two to three days to rule, according to the Thai Lawyers for Human Rights, an independent legal-aid group. 

The court ruled that the defendant’s actions were a disgrace to the king and dismissed his argument that the call for monarchy reform was meant to defend the protesters from police action, the group said.

Arnon was among dozens of pro-democracy activists charged under the draconian lese majeste law in 2021 when Thai authorities cracked down on protesters calling for the resignation of then Prime Minister Prayuth Chan-Ocha and initiating public discussion on the role of the monarchy.

According to Thai Lawyers for Human Rights, at least 257 people, including 20 under the age of 18, were charged under lese majeste between May 2020 and September 2023.

The upstart Move Forward Party, which won the largest number of seats in the May general election, was the only mainstream party to call for changes to the royal insult law. Pita Limjaroenrat, the party’s prime ministerial candidate, was blocked by the influential Senate and pro-royalist parties that oppose any changes to the law shielding the royals from criticism.

(Updates with details on bail request in fifth paragraph. An earlier version of this story corrected the amount of fine.)

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