In the case of National Labor Relations Board v. Mexia Textile Mills, Inc., 1949, the U.S Supreme Court ruled in favor of the National Labor Relations Board (NLRB). The NLRB had accused Mexia Textile Mills of unfair labor practices for refusing to bargain with a union that represented its employees. The company argued that it was not obligated to negotiate because there were doubts about whether the union truly represented a majority of its workers. However, these doubts arose from an anti-union speech given by one of their supervisors which led some employees to withdraw their support from the union. The court held that since this doubt was created by an unlawful act committed by Mexia's supervisor who threatened plant closure if workers joined unions, it could not be used as defense against bargaining with said Union. Therefore, despite any subsequent loss in membership or support for the Union following such threats would still require employer engagement in good faith bargaining under NLRA Act.

The dissenting opinion in the case of NATIONAL LABOR RELATIONS BOARD v. MEXIA TEXTILE MILLS, INC., 1949 argued that the majority's decision to uphold the National Labor Relations Board's (NLRB) order was incorrect because it failed to consider whether or not Mexia Textile Mills had engaged in unfair labor practices as defined by law. The dissenters believed that there was insufficient evidence presented at trial to prove that Mexia had interfered with its employees' rights under Section 7 of the National Labor Relations Act, which guarantees workers' right to self-organization and collective bargaining. They also disagreed with NLRB’s finding that Mexia violated Section 8(1) of this act by interfering with these rights through threats and coercion against union members. Furthermore, they contended that even if such interference did occur, it would not necessarily constitute an unfair labor practice unless it resulted in a restraint or coercion on employees’ rights – something which they felt was not adequately demonstrated during proceedings.