Incompetent lawmakers and transactional politics are fouling the legislative process, leading to shoddy laws and a host of constitutional challenges, according to one of the nation's top jurists.

Constitutional Court chief justice Mahfud MD said that the transactional politics took the form of deal making between members of the government and different parties in the House of Representatives (DPR).

"Another reason is the lack of professionalism of lawmakers," Mahfud said at a press conference about the court's performance in 2012 in Jakarta on Tuesday.

Other laws were brought before the court for judicial review to seek additional clarification or interpretation, such as the review of the Oil and Gas Law that led to the dissolution of upstream oil and gas regulator BPMigas, Antara news agency reported.