In the case of Board of Regents of the University of the State of New York v. Tomanio, 1979, the U.S. Supreme Court ruled that when a federal court is exercising its jurisdiction to hear and decide a state-law claim, it must apply state law or policy governing tolling (suspension) and related aspects of statutes limitations. The plaintiff in this case was John Tomanio who sued for violation his civil rights under Section 1983 after being denied admission to medical school by New York's Board Of Regents due to an alleged discriminatory quota system favoring in-state residents. However, he filed his lawsuit more than three years after his cause accrued which exceeded New York’s statute-of-limitations period for personal injury actions - upon which Section 1983 claims were based on at that time. Despite arguing that he had only discovered about this discrimination recently hence should be allowed additional time (tolling), both lower courts dismissed his suit as untimely without considering whether equitable tolling principles could extend filing deadline under federal law.

In the dissenting opinion for the case of Board of Regents of The University Of The State Of New York et al. v. Tomanio, Justice Brennan argued that federal courts should not be bound by state statutes when determining whether a plaintiff's civil rights claim is time-barred under Section 1983. He contended that such an approach would undermine Congress' intent to provide broad remedies for constitutional violations and could result in inconsistent applications of federal law depending on varying state rules. Furthermore, he noted that this decision contradicts previous Supreme Court rulings which held that federal law governs the characterization of claims brought under Section 1983. In his view, applying state statute-of-limitations laws to these cases was inappropriate because it allowed states to dictate how long victims had to file their lawsuits in federal court - something he believed was contrary to principles of national supremacy and uniformity within our legal system.