The case Employees of the Department of Public Health and Welfare of Missouri et al. v. Department of Public Health and Welfare of Missouri et al., 1972, revolved around a dispute between employees in the public sector (specifically those working for the state's health department) and their employer, over union dues being automatically deducted from their paychecks without explicit consent. The Supreme Court ruled that such automatic deductions were not unconstitutional as long as they were used solely for collective bargaining purposes rather than political activities, thereby upholding an earlier ruling by a lower court. This decision was based on the premise that while public employees have First Amendment rights to free speech and association, these do not extend to refusing financial support for legitimate employment-related negotiations conducted on their behalf by unions.

In the case of Employees of the Department of Public Health and Welfare of Missouri v. Department of Public Health and Welfare, Justice Marshall dissented from the majority opinion. He argued that public employees should not be denied their First Amendment rights to free speech simply because they work for a state agency. In his view, these workers have a right to express their views on matters related to their employment without fear of retaliation or punishment by their employer - in this case, the State itself. Furthermore, he contended that any restrictions on such speech must serve an important governmental interest and must be narrowly tailored so as not to infringe upon more speech than necessary. The dissenting justice believed that neither condition was met here; thus making it unconstitutional for Missouri's welfare department policy prohibiting its employees from criticizing it publicly.