This Day in Union History: 6/23/1947 Tuman’s Veto on The Taft-Hartley Act is overridden by Congress. The act amends the 1935 National Labor Relations Act by allowing states to exempt themselves from union requirements. Antiunion open shop laws are quickly passed in 20 states. llustration provided by USL Digital Libraries #SlaveLaborBill #LaborHistory #LaborValues #UnionHistory #UnionValues #WagnerAct #NLRA#tafthartley