In the case of Shepard v. National Labor Relations Board (NLRB) in 1982, the U.S Supreme Court ruled that an employer's refusal to hire union supporters did not constitute a violation of the National Labor Relations Act (NLRA). The court held that while Section 8(a)(3) of NLRA prohibits employers from discriminating against employees for their union activities or sympathies, it does not extend this protection to job applicants. This decision came after Robert Shepard was denied employment at several companies due to his known support and involvement with unions. He filed complaints with NLRB alleging unfair labor practices by these companies but both NLRB and subsequently the Supreme Court rejected his claims stating that NLRA protections apply only once an employment relationship has been established.

The dissenting opinion in the Shepard v. National Labor Relations Board case argued that the majority's decision to uphold an employer's right to fire striking workers was a misinterpretation of labor law and detrimental to collective bargaining rights. The dissenters believed that this ruling would discourage employees from exercising their legal right to strike, as it essentially allowed employers to retaliate against such actions with impunity. They also expressed concern over the potential for abuse by unscrupulous employers who might use this ruling as a means of suppressing union activity or intimidating workers into accepting unfavorable contract terms. Furthermore, they disagreed with the majority's assertion that replacement workers were necessary for maintaining operations during a strike, arguing instead that other options could be explored without resorting to termination of employment.