About 25 members of the National Legislative Assembly have signed a petition asking the Constitutional Court to rule on the organic bill on the election of MPs, Assemblyman Kittisak Ratanawaraha said on Wednesday.
Mr Kittisak, one of the signatories, said the move would have little effect on preparations for the general election.
The petition would be sent to NLA president Pornpetch Wichitcholchai, who would forward it to the court.
"I would like the Constitutional Court to give a clear ruling now, instead of the issue remaining alive until the promulgation of the law. If a request for a ruling were to be filed afterwards, there will be greater complications," he said.
The NLA could seek the court's ruling right away, and did not have to wait for Prime Minister Prayut Chan-o-cha to reject the bill and return it to them. The NLA's move was also in line with the prime minister's decision to have legal officials carefully check the bill before it is proposed to His Majesty the King, Mr Kittisak said.
NLA members wanted the court's ruling because many groups had reservations about some of the provisions. They included Meechai Ruchupan, chief of the Constitution Drafting Committee, Mr Kittisak said.
"It is not a conspiracy to delay the election... The request for a ruling by the Constitutional Court will not have a great impact on the election roadmap," he said.
A source at the NLA said 25-30 NLA members had signed the petition. It would be sent to the NLA president on Thursday and was likely to reach the court on Monday.
Most petitioners were NLA members who abstained or were absent when the chamber recently voted in favour of the bill's passage.
Topics needing clarification included a ban on the rights of political officials who failed to exercise their voting right and permission for election officials to mark ballots on behalf of voters with disabilities preventing them doing so themselves, the source said.
The source expected the court to give its decision two months after receiving the request.
The bill on the appointment of senators has already been referred to the court.
