The 1977 U. S. Supreme Court decision in Abood v Detroit Board of Education found that forcing public school employees to pay union dues affects their First Amendment rights. The Court held that a government employer and union may reach an agreement requiring employees to pay an agency service fee to cover the costs of collective bargaining, contract administration, and grievance adjustment. However, the decision clarified that objecting employees have a constitutional right to withhold payment of any union fees that support political and ideological causes.

In other words, those objecting employees can be compelled to pay only those expenses directly related to collective bargaining. Under Abood, all public employees have a constitutional right to "prevent the Union's spending a part of their required service fees to contribute to political candidates and to express political views unrelated to its duties as exclusive bargaining representative."111

School boards that negotiate contracts requiring employees to pay union representation fees are acting within their own discretion to force employees to join unions and are therefore legally liable for any failure to protect the rights of objecting employees. Under Abood, employees must be given the clear choice of either joining the union and paying full dues or else paying only a service fee to cover the direct costs of collective bargaining. Contracts that fail to give employees this choice violate the employees' constitutional rights.