The Office of the Ombudsman will ask the Constitutional Court to rule whether recent summonses issued by the Sereepisuth Temeeyaves-led House committee on corruption violated the charter.
The summonses in question were issued on Wednesday for Prime Minister Prayut Chan-o-cha and Deputy Prime Minister Prawit Wongsuwon.
Gen Prayut is required to why he failed to complete reciting the oath of office in July and issues regarding the 2020 budget. Gen Prawit's role in formulating the current budget is also being questioned.
The committee voted six to three to issue the summonses after the premier and his deputy previously sent representatives to answer questions on their behalf.
It said Section 129 of charter relating to Lower House and Senate procedures allowed it to do so.
However, this is being questioned by the Office of the Ombudsman. Its secretary-general, Raksagecha Chaechai, said yesterday that the Constitutional Court will be asked to examine the section and rule whether the summonses are legitimate.
"We need a court ruling on these summonses to set a precedent for committees," Mr Raksagecha said.
The ombudsman's move is in response to a complaint lodged by Palang Pracharath MP Paiboon Nititawan who claimed the Sereepisuth committee has no authority to summon Gen Prayut and Gen Prawit.
Mr Paiboon pointed to the Constitutional Court's ruling on the oath-taking controversy that said the issue was beyond the authority of any organisation under the constitution to examine it.
The Seri Ruam Thai Party leader has doggedly pursued the prime minister over his incomplete oath recital during the cabinet's swearing-in ceremony in July, saying the blunder disqualified Gen Prayut from putting the 3.2-trillion-baht budget bill before parliament this month.
However, Palang Pracharath MP for Bangkok and committee member Sira Jenjaka thinks Pol Gen Sereepisuth may have abused his power out of personal animosity towarsds Gen Prayut.
"I'm upset by the actions of the committee chairman," he said, adding Pol Gen Sereepisuth should be spending time going after truly corrupt officials.
Mr Sira said his colleagues will next week propose the committee chairman be replaced.
Also "in a bid to seek clarity," he said he and four government MPs sitting on the committee, has asked the House speaker to decide whether the summonses for Gen Prayut and Gen Prawit violate parliamentary regulations.