The case study explores the ways in which one police union (New York City's Patrolmen's Benevolent Association) used the judicial system to influence one type of departmental policy--entry-level, personnel selection procedures--in the early 1970's. The study identifies the reasons why the union chose to influence selection policy by using the court system rather than by using legislative or administrative channels. The study suggests that two political conditions facilitate a police union's decision to influence policy by using the judicial system. First, the union must face a formidable array of opponents, including, but not limited to, the mayor and police commissioner. The mayor and police commissioner must have publicized their positions and must have a high political stake in avoiding compromise. This combination of circumstances makes it unlikely that the union will be able to attain its objectives through the traditional collective bargaining process unless it is willing to make drastic concessions in other policy areas. Also, the union is more likely to turn to the court system if the strategy of the union's opponents includes access to Federal resources, such as Federal funds or use of the Federal court system. In this event, the union is generally preempted from securing a policy victory by traditional collective bargaining or lobbying at the State legislature. Resort to the judicial system may have the following effects on the type of policy eventually adopted: (1) it may limit the opportunity for compromise; and (2) it may lead to apolitical, technical solutions for political problems. Seven footnotes and 15 references are listed.