The Criminal Court on Tuesday sentenced Arnon, 39, to four years in jail for participating in a political protest in 2020, during which he called for public debate on the role of His Majesty the King.
Arnon was also found guilty of breaching the emergency rules imposed in order to curb the Covid-19 outbreak but was acquitted of seven other charges, said his lawyer, Krisadang Nutcharus.
Krisadang said he posted 200,000 baht cash as bail for Arnon while the defendant prepared to appeal, but bail was denied by the court on the grounds that he might escape.
Thailand’s lese majeste law is Article 112 of the Criminal Code. The law states that whoever defames, insults or threatens the King, the Queen, the heir-apparent or the regent, will be punished with imprisonment of three to 15 years.
In 2021, Time magazine named Arnon among its influential “Time 100 Next” list of emerging leaders shaping the future. Arnon was praised for his leadership of the youth-led pro-democracy anti-government movement.