In Gardner v. Westinghouse Broadcasting Co., the Supreme Court examined whether a Pennsylvania statute that prohibited discrimination based on age was pre-empted by the Age Discrimination in Employment Act (ADEA). The plaintiff, Charles Gardner, alleged that he had been fired from his job at Westinghouse Broadcasting because of his age. He initially filed suit under both federal and state law but later dropped his federal claim to pursue relief solely under Pennsylvania's anti-discrimination law. However, the lower courts dismissed his case on grounds that ADEA superseded or preempted state laws dealing with age discrimination. The Supreme Court disagreed with this interpretation and held unanimously for Gardner. It ruled that Congress did not intend for ADEA to displace any existing state laws when it enacted its own legislation against age-based employment discrimination; instead, it aimed to supplement them. Therefore, individuals could still seek remedies under their respective states' statutes even if they were also covered by ADEA.

In the dissenting opinion for Gardner v. Westinghouse Broadcasting Co., Justice Rehnquist disagreed with the majority's decision to allow a claim of sex discrimination under Title VII of the Civil Rights Act based on an employer's refusal to hire women who were pregnant. He argued that pregnancy was not a gender-specific condition, but rather a voluntary and temporary disability that could affect both men and women indirectly or directly respectively. Therefore, he contended that it should be treated like any other non-job-related physical condition in terms of employment decisions. Furthermore, he expressed concern about judicial overreach by interpreting legislation beyond its intended scope as defined by Congress.