
Jumpol, 66, pleaded guilty at the Nakhon Ratchasima Provincial Court Friday.
With his head shaven, he showed up at the court in a brown inmate uniform and expressed an intention to not fight his charges. He did not seek the help of any lawyer.
The conviction against him was related to a resort home he had built in the Thap Lan National Park.
Due to his confession, the court commuted his six-year jail term to just three years.
Jumpol, however, was also ordered to have the resort home demolished and to pay more than Bt892,000 compensation to the state.
After the court delivered the verdict, he was brought to the Bangkok Remand Prison.
It was announced in the Royal Gazette on March 7 that Jumpol has been stripped of all royal decorations and the police-general rank since February 27.