What are the conditions for a law made by a State Legislature to prevail over an existing law or a law made by Parliament with respect to one of the matters enumerated in the Concurrent List?
The conditions for a law made by a State Legislature to prevail over an existing law or a law made by Parliament with respect to one of the matters enumerated in the Concurrent List are:

1. The law made by the Legislature of a State must not be repugnant to any provision of a law made by Parliament which Parliament is competent to enact, or to any provision of an existing law with respect to one of the matters enumerated in the Concurrent List.
2. The law made by the Legislature of a State must have been reserved for the consideration of the President and received his assent.