In the case of Johnson et al. v. Mayor and City Council of Baltimore et al., 1984, the U.S Supreme Court dealt with a dispute over retirement benefits for city employees in Baltimore, Maryland. The plaintiffs were retired firefighters and police officers who argued that changes made to their pension plans by the city violated their contract rights under Article I, Section 10 (the Contract Clause) of the United States Constitution. They claimed that these modifications reduced their benefits without providing them any additional advantages or compensation in return. However, both lower courts ruled against them stating that they did not have an enforceable contractual right to unaltered pensions because such promises were not explicitly stated in legislation when they retired. The Supreme Court affirmed this decision on appeal; it held that unless there is clear evidence showing a legislative intent to create private contractual rights through statute or ordinance, public employees cannot claim those rights are protected by the Contract Clause from subsequent modification or impairment.

In the dissenting opinion for Johnson et al. v. Mayor and City Council of Baltimore et al., Justice Brennan, joined by Justices Marshall and Blackmun, argued that the majority's decision to uphold a city ordinance requiring non-resident municipal employees to pay a "commuter tax" violated the Privileges or Immunities Clause of the Fourteenth Amendment. The dissenters contended that this clause protects citizens from discrimination based on their residency status when it comes to fundamental rights such as employment. They asserted that working for one's government is a basic right of citizenship and should not be subjected to discriminatory taxation policies based solely on where an individual lives. Furthermore, they disagreed with the majority’s view that there was no constitutional violation because residents also paid taxes; instead, they believed this constituted double taxation for non-residents who already paid taxes in their home jurisdictions.