Former Thai leader Thaksin Shinawatra was formally charged in a royal insult case Tuesday, part of a series of legal cases that threaten to plunge the Southeast Asian country into political turmoil.

Thaksin, a two-time former prime minister and the de facto leader of the ruling Pheu Thai party, was arraigned under Thailand’s stringent lese majeste law that protects the royal family from criticism, according to a spokesman with the attorney general’s office.

While the outcome of the case is far from certain, the litigation poses risks to the less-than-year-old government that was formed after a messy general election last year. They also signal the possible unraveling of a deal that saw Pheu Thai and a clutch of pro-royalist and military-aligned parties joining hands to take power and paving the way for Thaksin’s return from a 15-year exile.