Create a new independent body with a chairman directly appointed by the Chief Justice of The Supreme Court. Allow the body to take suo moto cognisance of corruption cases involving a sitting member of a central or state legislative body. Set up a special, fast track judicial process for cases prosecuted by this body. In its founding charter, make it especally clear that it must respond to RTI requests and specify penalties for its officials if they fail to do so. And finally give this body over-riding authority over state police machinery to help it overcome political interference.
If you do this, every minister going forward will have second thoughts about corruption, certainly after the first couple of successful prosecutions. You will have single handedly done more to fight corruption than any public figure in living memory. And you may just be responsible for the dawn of a new political culture in India.