In the case of Richardson-Merrell Inc. v. Koller, 1984, the Supreme Court ruled in favor of a pharmaceutical company against claims made by an infant plaintiff who had suffered birth defects allegedly caused by a drug her mother took during pregnancy. The court held that federal law preempted state law on this issue and thus barred any claim for damages based on failure to warn about potential risks associated with the drug's use during pregnancy. This decision was significant as it established that manufacturers could not be held liable under state tort laws if they complied with FDA regulations regarding warnings about their products' potential dangers.

In the dissenting opinion for Richardson-Merrell Inc. v. Koller, Justice Blackmun argued that federal law should not preempt state tort claims regarding prescription drugs' safety and efficacy. He contended that Congress did not intend to create a blanket immunity for drug manufacturers from state-law damages suits when it enacted the Federal Food, Drug, and Cosmetic Act (FDCA). Instead, he believed that such lawsuits could coexist with FDA regulation without undermining federal objectives or creating an undue burden on interstate commerce. Furthermore, he suggested that allowing these suits might actually further congressional intent by providing additional incentives for drug companies to ensure their products are safe and effective. The majority's decision in this case effectively shielded pharmaceutical companies from liability under state law if they complied with FDA regulations - a position which Justice Blackmun strongly disagreed with.