In the 1998 case of Teresa L. Cunningham v. Hamilton County, Ohio, the U.S Supreme Court addressed a dispute over whether an individual could sue a county for alleged violations of federal law under Section 1983. The plaintiff, Teresa Cunningham, claimed that her constitutional rights were violated when she was fired from her job at the Hamilton County Clerk's office after taking medical leave due to stress and depression. She argued that this action constituted discrimination based on disability in violation of the Americans with Disabilities Act (ADA). However, Hamilton County contended it had immunity from such lawsuits under Section 1983. The court ruled in favor of Cunningham by stating that local governments are not immune from suits brought against them for violating federal laws unless Congress has explicitly granted such immunity - which they did not do so in this case regarding ADA claims. This ruling clarified how Section 1983 applies to counties and other local government entities; essentially holding them accountable for any potential violations of federal law unless specifically exempted by Congress.

In the dissenting opinion for Teresa L. Cunningham v. Hamilton County, Ohio, it was argued that the majority's decision to uphold a lower court ruling denying Ms. Cunningham's claim of gender discrimination in her termination from employment was flawed. The dissenting justices believed that there were indeed genuine issues of material fact regarding whether or not Ms. Cunningham had been treated less favorably than similarly situated male employees and thus should have been allowed to proceed with her case at trial level rather than being dismissed on summary judgment as per the lower court’s decision. The dissenters pointed out several instances where they believe evidence suggested possible discriminatory treatment based on sex such as inconsistent reasons given for her firing and alleged preferential treatment towards male colleagues who committed similar infractions but received lesser punishments or none at all. They also disagreed with the majority's interpretation of what constitutes "similarly situated" when comparing different employees' conduct and subsequent disciplinary actions taken by employers which they felt too narrowly defined thereby limiting potential claims of discrimination unfairly.