Former deputy premier Plodprasop Suraswadi was sent to jail on Thursday after appearing at the Supreme Court for his sentencing for abuse of power.
His appearance on Thursday followed a warrant which was issued for him last month after he failed to show up at the Supreme Court to hear the court strike down his appeal against a two-year prison sentence.
In 2018, the Appeal Court increased a one-year suspended sentence originally handed to Plodprasop by the Central Criminal Court for Corruption and Misconduct Cases, arguing his actions constituted a "severe offence" which caused damage to the state administration.
Plodprasop, while serving as permanent secretary for the environment, was found guilty of violating Section 157 and Section 84 of Criminal Code for reversing the promotion of senior official Vitoon Chalayonnawin to economic forest promotion director and influencing Damrong Pidech, then chief of the Royal Forest Department, to have Mr Vitoon demoted to a lower-ranking post in 2003.
Mr Vitoon was eventually transferred to work as a provincial forestry official in Amnat Charoen province.
The court then handed the former deputy prime minister a two-year jail term without suspension and awarded the plaintiff, Vitoon Chalayonnawin, 1.4 million baht in compensation.
After acknowledging his sentence on Thursday, he was escorted to the Bangkok Special Prison.
The Appeal Court on Thursday also overturned a Criminal Court ruling and handed former Department of Special Investigation chief Tarit Pengdith and three other defendants a two-year jail sentence for committing malfeasance and intentional defamation.