The Constitutional Court ruled on Wednesday that Thammanat Prompao’s conviction in an Australian drugs case does not disqualify him from holding his posts as a Palang Pracharath Party MP and deputy agriculture minister.
The court said that under the sovereignty principle, Thai laws do not cover legal cases that occur overseas.
Prompao has threatening to file about 100 defamation lawsuits against individuals and organisations who dug up his criminal past and questioned his educational background, noting that the allegations were part of a political ploy to discredit him.
Australian court documents, seen in a BBC show, revealed that Thammanat admitted to conspiring to import a commercial quantity of heroin to Australia on November 15, 1993.
An Australian judge handed down the verdict in March 1994 and sentenced Thammanat to six years in jail. Thammanat was deported from Australia after being imprisoned for four years in Sydney, BBC Thai reported.