Even the appointment of Mukherjee on the panel has been opposed by civil rights groups.

The 20-year-old tribal woman was allegedly raped by more than a dozen men Monday night in Subalpur village in Birbhum district, some 180 km from Kolkata. Thirteen people have been arrested so far.

The woman admitted to a hospital with critical injuries was subjected to the brutality on the order of a kangaroo court which held her guilty of having an affair with a man outside her community.