(A) Provisions of the Panchayats (Extension to the Scheduled Areas) Act (40 of 1996) , S.4(g)— Jharkhand Panchayat Raj Act (6 of 2001) , S.21(B), S.40(B), S.55(B)— Panchayats in scheduled areas - Office of chairperson at all levels - Exclusive reservation in favour of scheduled Tribes - Not unconstitutional. Constitution of India , Art.243M, Art.16— In Panchayats located in Scheduled Areas, the exclusive representation of Scheduled Tribes in the Chairperson Positions of the same bodies is constitutionally permissible. This is so because Article 243-M(4)(b) expressly empowers Parliament to provide for 'exceptions and modifications' in the application of Part IX to Scheduled Areas. The provisos to S. 4(g) of the PESA 1996 contemplate certain exceptions to the norm of 'proportionate representation' and the same exceptional treatment is incorporated in the provisions of State Act (JPRA). Sections 21(b), 40(B) and 55(B) of the JPRA to reserving office of Mukhiya) (at Gram Panchyat level), Pramukh (at Panchayat Samithi level) and Adhyaksh (at Zila Parishad level) for Scheduled Tribes is not unconstitutional.(Para 23) The 100% reservation made in favour of S.T. cannot be faulted on ground that the maximum reservation which is legally permissible is only up to 50 per cent. The rule that reservation should not exceed 50% ....