13. Such a scheme would, in our view, present considerable constitutional disadvantages and anomalies. It would be very difficult to work a CentralExecutive and Legislature in which some Ministers, who dealt with Compulsory’ subjects, were responsible to the whole of India while other Ministers, who dealt with Optional subjects, would be responsible only to those Provinces which had elected to act together in respect of such subjects. This difficulty would be accentuated in the Central Legislature, where it would be necessary to exclude certain members from speaking and voting when subjects with which their Provinces were not concerned were under discussion. Apart from the difficulty of working such a scheme, we do not consider that it would be fair to deny to other Provinces, which did not desire to take the optional subjects at the Centre, the right to form themselves into a group for a similar purpose. This would indeed be no more than the exercise of their autonomous powers in a particular way.