The case of the National Labor Relations Board v. Kentucky River Community Care, Inc., et al., 2000 revolved around the definition and classification of "supervisor" under Section 2(11) of the National Labor Relations Act (NLRA). The Supreme Court was asked to decide whether certain nurses at a mental health facility were supervisors or employees. The distinction is crucial because supervisors are not protected by NLRA provisions that safeguard collective bargaining rights for employees. The NLRB had ruled that these nurses were not supervisors as they used professional judgment rather than independent managerial authority in directing less-skilled employees. However, Kentucky River Community Care argued that these nurses did exercise supervisory functions when overseeing other staff members during their shifts. In a unanimous decision, the Supreme Court held that exercising professional or technical judgment while directing less-skilled workers could qualify an individual as a supervisor under NLRA if it involved responsibly directing them with accountability for their performance on behalf of management. This ruling effectively broadened who can be considered a supervisor and thus potentially excluded from union membership.

In the dissenting opinion for the case of National Labor Relations Board v. Kentucky River Community Care, Inc., Justice Stephen Breyer argued that the majority's interpretation of "supervisor" was too broad and could potentially include many employees who have only minor supervisory duties. He contended that this would undermine collective bargaining rights under the National Labor Relations Act (NLRA). According to him, a supervisor should be someone with genuine managerial authority who can hire, fire or discipline other workers. The majority’s decision to classify professional nurses as supervisors because they direct less-skilled employees in their work tasks is inconsistent with Congress' intent when it enacted NLRA. This ruling may exclude large numbers of professionals from its protection and weaken labor unions by reducing their potential membership base.