Seventy six legislators, 43 senators and 33 Democrat MPs, have asked the Constitution Court to rule whether the Public Private Partnership (PPP) legislation passed by parliament is constitutional.
The PPP Bill has already been passed by parliament and is currently awaiting royal endorsement to become law.
Paibul Nititawan, an appointed senator, and Democrat MP Wirat Kalayasiri, on Thursday morning submitted a petition through Parliament President Somsak Kiatsuranont to the Constitution Court seeking a ruling on the constitutionality of the bill.
Mr Paibul said the bill, if enacted into law, would give legitimacy to and support the government's 2.2 trillion baht infrastructure loan bill now being deliberated in the House of Representatives.
The Public Private Partnership Bill enables the government to work with private operators on infrastructure projects using state budgets without parliamentary scrutiny, he said.
Mr Paibul said the legislation may violate Sections 75, 78, 84, 87 and 169 of the constitution.
He believed Mr Somsak would quickly forward the petition to the Constitution Court after verifying it.
If the court rules that the PPP Bill is unconstitutional, the government would have difficulty pushing the infrastructure loan bill through parliament.