
Prasong was convicted for defamation relating to his newspaper article criticising the Constitution Court judges for acquitting former prime minister Thaksin Shinawatra on the asset concealment case in 2001.
The Criminal Court sentenced Prasong to serve one year in jail and ordered him to pay a fine of Bt7,000. The imprisonment was suspended for one year.
The appellate review stood by the lower court's decision although the sentence suspension was extended to two years.
Prasong said he would lodge a final appeal with the Supreme Court.