BANGKOK (AP) — Thailand’s state Election Commission said Wednesday it concluded there is evidence that the top candidate to become the country’s next prime minister, Move Forward Party leader Pita Limjaroenrat, violated election law and referred his case to the Constitutional Court for a ruling.

The commission’s decision, announced in a press release, means the court could order Pita to be suspended from his duties as a Member of Parliament until the ruling is issued. In theory it does not rule out him being nominated to become prime minister by Parliament on Thursday, because the post does not have to be held by a lawmaker. But it makes his confirmation by a vote in Parliament, which was already uncertain, even less likely.

The Move Forward Party swept to a surprise first-place finish in May’s general election, capturing 151 seats in the 500-member House of Representatives and the most popular votes. Move Forward has assembled an eight-party, 312-seat coalition it had planned to take power. But the unlikely approval from members in the conservative 250-seat unelected Senate, which participates in the vote for prime minister, makes Pita’s path to power a difficult one.

The case against Pita hinges on his alleged ownership of shares in a media company, which would bar him from running for office. The complaint against him, lodged by a member of a rival political party, applied to the period of the 2019 general election. Pita had challenged the basis for the claim, which extended to his failure to include the shares on a mandatory assets declaration.

The case the commission referred to the court goes beyond a technical election law violation and accuses Pita of running for office with awareness that he was ineligible, a criminal violation punishable by maximum imprisonment of three years and/or a fine of up to 60,000 baht ($1,720). The party faces a fine of up to 100,000 baht ($2,865).

Caretaker Deputy Prime Minister Wissanu Krea-ngam, the government’s top legal advisor, has been quoted as saying that if party leader Pita was ruled unqualified to endorse his party’s candidates for the May election, the polls could be nullified and a new election called.

There have been fears since the election that Thailand’s conservative ruling establishment would use what its political opponents consider to be dirty tricks to hold on to power. For a decade-and-a-half, it has repeatedly used the courts and so-called independent state agencies such as the Election Commission to issue controversial rulings to cripple or sink political opponents.

The dissolution in 2019 of the Future Forward party, a forerunner of Move Forward, triggered vigorous street protests by pro-democracy activists that trailed off only when the coronavirus pandemic took hold.