Law Minister Ravi Shankar Prasad Tuesday said the NDA government is "working out" a plan to make parliament taint free, as promised by Prime Minister Narendra Modi.Modi, in a speech in the Rajya Sabha, committed to make parliament taint free, adding that cases against MPs should be decided on within one year."The prime minister has taken it up very seriously. We are working it out," Prasad said, responding to a question."The prime minister wants to change India's polity," he said during an interaction with women journalists at Indian Women's Press Corps (IWPC).The Supreme Court in a judgment given March 10, directed all trial courts to expedite and conclude cases against MPs and state legislators within one year from the date of framing of charges.Thinktank Association for Democratic Reforms (ADR) analysed the affidavits of 541 newly-elected MPs, of whom 53 have declared criminal cases where charges have been framed.The BJP, with a simple majority of its own in the Lok Sabha, has also the largest number (24) of MPs with criminal cases against them.