Thailand’s Constitutional Court is set to decide Wednesday whether popular politician Pita Limjaroenrat, who was blocked from becoming prime minister, should now lose his seat in Parliament.

The election victory last year by Pita’s progressive Move Forward party reflected a surprisingly strong mandate for change among Thai voters after nearly a decade of military-controlled government. But the party was denied power by members of the unelected and more conservative Senate.

Pita was suspended from his lawmaking duties pending the court ruling Wednesday on whether he violated election law due to his ownership of shares in ITV, a company that is the inactive operator of a defunct independent television station. By law, candidates are prohibited from owning shares in any media company when they are registered to contest an election.

The Senate, whose members are appointed by the military, cast votes to choose a prime minister, under a constitution that was adopted in 2017 under a military government. The Move Forward party now heads the opposition in Parliament.