Subsidiarity and Public Purchasing: Who should Apply Competition Law to Collusive Tendering and How Should They Do it? - European Public Law View Subsidiarity and Public Purchasing: Who should Apply Competition Law to Collusive Tendering and How Should They Do it? by - European Public Law Subsidiarity and Public Purchasing: Who should Apply Competition Law to Collusive Tendering and How Should They Do it? 4 1 European Public Law