Senator Somphan Palasak on Tuesday threatened legal action against iLaw director Yingcheep Atchanont over allegations that he was ineligible to contest the Senate election under the business owner category.
Mr Somphan said the allegations were first made more than two years ago and that both he and fellow senator Daeng Kongma, also from Amnat Charoen, had already been cleared by the Election Commission (EC).
He said the EC had ruled that he and Ms Daeng met the eligibility requirements for Group 10 candidates and that they would file criminal complaints against Mr Yingcheep for allegedly damaging their reputations.
The dispute followed a Facebook post by Mr Yingcheep questioning whether the two senators qualified under Group 10, which covers enterprise owners outside the small and medium-sized enterprise category under Senate rules.
In his post, Mr Yingcheep said that Mr Somphan described himself in his application as a chicken noodle vendor while Ms Daeng listed herself as a pork vendor. He said neither appeared to operate a business large enough to qualify under the category, which he claimed applies to operators with more than 300 employees.
Mr Somphan questioned why Mr Yingcheep interpreted Group 10 as applying only to owners of businesses larger than SMEs.
He said Mr Yingcheep should respect the EC's ruling and refrain from raising issues that had already been settled in a way that could mislead the public.
Under the 2024 Senate election system, the 200 senators were selected from 20 professional groups, with 10 senators representing each group. Group 10 covers enterprises that are not classified as SMEs.
Meanwhile, Deputy Prime Minister Songsak Thongsri, one of nine people named by iLaw as allegedly being part of a network involved in Senate election collusion, said he would file a criminal defamation complaint with police in Bueng Kan, his hometown. Those named by iLaw include Mr Songsak, Prime Minister Anutin Charnvirakul, Transport Minister Phiphat Ratchakitprakarn and several other cabinet ministers and senior party figures.
