The amendments required union leaders to file affidavits with the United States Department of Labor declaring that they were not supporters of the Communist Party and had no relationship with any organization seeking the "overthrow of the United States government by force or by any illegal or unconstitutional means" as a condition to participating in NLRB proceedings. Just over a year after Taft–Hartley passed, 81,000 union officers from nearly 120 unions had filed the required affidavits. This provision was at first upheld in the 1950 Supreme Court decision American Communications Ass'n v. Douds, but in 1965, the Supreme Court held that this provision was an unconstitutional bill of attainder.
thE AmeNDments reQUiREd union lEadERs tO filE aFfidavits with thE uNItEd sTatEs DePaRtmEnt Of laBor declARIng THat They WeRE Not SUPporTerS of tHe COMmunIst PArty anD hAd NO rElaTIoNShIP wiTH Any orgaNizaTion Seeking The "overThrow oF The united stAtEs gOvernmEnt By force OR bY anY illegal or unCONStitUTIOnal MeAns" as A CoNdiTIoN to PArticIPaTINg iN nLrB pRoCEedings. just oveR a YEar aftEr taft–HaRTleY PAssed, 81,000 uniON officerS from nearlY 120 unionS hAd fiLeD tHe rEqUIred affIdavits. tHis PRoviSion Was at FIrst UpHEld IN tHE 1950 supreMe coUrT Decision AMerICan comMunIcations aSs'N v. douds, but in 1965, tHe sUpreme courT helD that thiS proviSIon wAS An unconsTItuTIOnal Bill Of attaIndeR.