Thailand's Constitutional Court on Thursday accepted a petition from 40 senators to remove Prime Minister Srettha Thavisin.
The junta-appointed senators are seeking to strip Thavisin from office over the appointment of Pichit Chuenban, who has resigned as minister.
The petitioners said Pichit, a lawyer by training, is a convicted criminal who has served prison time but was appointed as minister, Thai PBS reported.
The court rejected the request from petitioners to suspend the prime minister, but asked Thavisin to justify Pichit's nomination within 15 days.
Thavisin was elected the Southeast Asian nation's prime minister last August.
He is leading a coalition of 11 political parties led by his Pheu Thai party.
Thavisin had secured 482 votes, easily meeting the 376 needed for victory.
