Former Thai Prime Minister Thaksin Shinawatra and his daughter Paetongtarn Shinawatra arrive at the Supreme Court ahead of a verdict on the legality of Thaksin's six-month hospital stay before he was granted a parole, in Bangkok, Thailand, September 9, 2025. REUTERS/Athit Perawongmetha
Former Thai Prime Minister Thaksin Shinawatra is escorted by corrections officers after the supreme court ruled to return Thaksin to prison for one year, in the case of his unlawful six-month hospital stay before he was granted parole, in Bangkok, Thailand, September 9, 2025. REUTERS/Panumas Sanguanwong

By Devjyot Ghoshal and Panu Wongcha-um

BANGKOK (Reuters) - A smiling Thaksin Shinawatra arrived at Thailand's Supreme Court on Tuesday morning in his black and silver Mercedes Maybach luxury sedan, dressed in a dark suit and a yellow tie.

But the former Thai prime minister left the court complex bereft of the trappings of power, escorted into a plain silver van by Corrections Department officials, the collar of his white shirt unbuttoned and cuffs folded up.

After nearly two decades of dodging punishment, Thailand's most influential and polarising politician must now serve a prison term - the country's first ex-premier to face jail.

"I humbly accept and am ready to enter the (judicial) process after today's verdict," Thaksin said in a statement, soon after judges read out their decision in court.

"Even as I lose my freedom today, I still have the freedom of thought to benefit the country and the people."

The verdict is another hammer blow for the 76-year-old billionaire who has remade and dominated politics in Thailand for a quarter century, but has seen his once formidable influence dramatically whittled down in just a matter of weeks.

Late last month, his daughter and protégé Paetongtarn Shinawatra was sacked as prime minister by the constitutional court, triggering a scramble for power in which Thaksin's Pheu Thai party was decisively beaten by a former coalition partner.

Pushed out of power, haemorrhaging the public support that once made him unstoppable and now facing the very real possibility of a year in prison, this may be the lowest point in Thaksin's already turbulent political career.

"This is quite heavy," an emotional Paetongtarn said while walking out of court. "Me and my family are concerned about my father."

Paetongtarn had stood by her father in August 2023, when he made a dramatic homecoming following 15 years in self-imposed exile.

Immediately after landing in his private jet, Thaksin was transferred to prison to serve an eight-year sentence on charges of abuse of power and conflicts of interest from his time in office.

But he was moved out of jail and admitted to a hospital within hours, complaining of chest pain and high blood pressure.

The sentence was later reduced to only a year by the king and Thaksin was released on parole after just six months, all of it spent in the VIP wing of a hospital - a stay that the Supreme Court deemed unlawful on Tuesday, sending him back to prison.

"He won't be a decisive figure like in the past," said Titipol Phakdeewanich, a political science professor at Ubon Ratchathani University.

"This doesn't mean that he will disappear 100%, but it will now be difficult for him to make a big comeback."

MAVERICK POLITICIAN

The son of a merchant family from Thailand's north, Thaksin spent time in the police and then ran businesses, before making it big in the telecommunications industry to become one of the country's richest men.

He entered politics in the 1990s and within a decade found his way to the premiership, on the back of populist promises - including debt relief and low-cost health care - that led to a convincing win for his Thai Rak Thai party in the 2001 polls.

Thaksin rolled out those measures - part of his 'Thaksinomics' - to build an enduring base among Thailand's urban poor and rural voters, who brought him back with a landslide election victory in 2006.

By then, the maverick politician had already invited the ire of the powerful royalist-conservative establishment, setting the stage for a decades-long struggle marked by sometimes violent street protests, military coups and court decisions that dismissed Pheu Thai prime ministers.

Thaksin himself was ousted from power by a military coup in 2006, after the expansion of his business empire during his term sparked public anger and protests in the capital.

Even from exile, he helped his sister, Yingluck Shinawatra, secure the premiership in 2011 and then guided the Pheu Thai to form a government in 2023, eventually leading to Paetongtarn becoming prime minister.

The two are among the six Thai premiers from or backed by the Shinawatra family to be removed by the military or judiciary in the last 20 years, a sign of the relentless tussle between the clan and the conservative elites.

But Thaksin will be the first to spend time in jail.

"He was a juggernaut. And he's been exhausted, outlasted by his opponents, by the establishment," said Thitinan Pongsudhirak, a political scientist at Bangkok's Chulalongkorn University.

"They've taken him apart."

(Reporting by Devjyot Ghoshal and Panu Wongcha-Um; Editing by Saad Sayeed)