Bangkok, Sept. 9 -- Thailand's Supreme Court ruled on Tuesday that former Prime Minister Thaksin Shinawatra was unlawfully allowed to stay in hospital detention and should return to prison to complete his sentence.

The court's Criminal Division for Holders of Political Positions concluded that Thaksin's six-month hospital stay cannot be counted as time served for a one-year sentence.

"The time spent at a police hospital cannot be deducted as days of imprisonment," the court statement said.

"The defendant must therefore serve the prison sentence for one year according to a royal decree," it said.

Thaksin returned to Thailand in August 2023 after over 15 years of self-imposed exile. Upon arrival, he was taken into custody to serve an 8-ye...