Held that a local government did not have authority to prohibit labor union arrangements called agency-shop, hiring hall, and checkoff agreements. A municipality in Illinois asserted that it had the right to ban these practices under National Labor Relations Act section 14(b), which permits states to bar compulsory union membership as a condition of employment. Disagreeing, the Seventh Circuit held that the authority conferred in section 14(b) does not extend to the political subdivisions of states. The panel affirmed that the ordinance here was preempted by federal law.