The U.S. Supreme Court case National Labor Relations Board v. City Disposal Systems, Inc., 1983 revolved around the interpretation of Section 7 of the National Labor Relations Act (NLRA). The dispute began when a truck driver was fired by City Disposal Systems for refusing to drive a vehicle he believed was unsafe, an action he argued was protected under his union's collective bargaining agreement. The National Labor Relations Board (NLRB) agreed with him and ruled that his dismissal constituted an unfair labor practice as it violated Section 7 rights which protect "concerted activities" for employees' mutual aid or protection. However, this decision was overturned by the Sixth Circuit Court on grounds that individual actions do not qualify as "concerted activities". Upon reaching the Supreme Court, it reversed the lower court’s ruling in favor of NLRB's broader interpretation of Section 7 rights - stating that even if an employee acts alone but invokes a right grounded in their collective bargaining agreement, such activity can be considered “concerted”. Therefore, firing someone over such issues could indeed constitute an unfair labor practice.

In the dissenting opinion for the National Labor Relations Board v. City Disposal Systems, Inc., Justice Powell argued that an individual employee's action cannot be considered concerted activity protected by Section 7 of the National Labor Relations Act unless it is engaged in with or on behalf of other employees and not solely by and on behalf of the employee himself. He contended that interpreting "concerted activities" to include actions taken by a single employee would stretch its meaning beyond what Congress intended when drafting this legislation. Furthermore, he expressed concern about potential adverse effects such a broad interpretation could have on employers' ability to maintain discipline and productivity within their workforce.