stiffler,
I dont think anyone here accuses PM of a direct involvement in Mr Tiwari's murder. But, being the chairman of council of ministers, he should not let any of its member to obstruct the govt machinery in the process of filing a criminal case. If he does so then blame goes the PM for not being able to maintain a rule of law and for protecting a criminal. Lets hope PM will soon fire Prabhu shah or Mr shah will just resign. Only after that an impartial investigation will follow.