On August 4 2015, Chonsawat was convicted in cheating the Mueang Samut Prakan municipality election in 1999. He was sentenced to be one year and six months in jail.
His sentence was reduced by five months as part of a royal pardon this year.
He has been jailed for one year and one month.
Wasant said Chonsawat did not receive any privilege and he was released in normal procedure like other inmates.