In the case of Janet Reno, Attorney General, et al. v. Charlie Condon, Attorney General of South Carolina, et al., 1999, the U.S Supreme Court ruled in favor of the federal government's right to regulate state activities when they impact interstate commerce. The case revolved around a dispute over the Driver's Privacy Protection Act (DPPA), which prohibits states from disclosing personal information collected by motor vehicle departments without an individual’s consent. South Carolina challenged this law as a violation of states' rights under principles of federalism and argued that it was unconstitutional for Congress to impose such regulations on state governments. However, the court held that DPPA is constitutional because it regulates how states can participate in interstate commerce by selling driver data across state lines.

In the dissenting opinion for Reno v. Condon, Justice Stevens argued that the Driver's Privacy Protection Act (DPPA) did not violate principles of federalism as it was a valid exercise of Congress' power under the Commerce Clause. He contended that personal information has economic value and its sale or release by state DMVs constitutes a commercial activity subject to federal regulation. Moreover, he pointed out that DPPA does not compel states to enact any laws or regulations but merely prohibits certain conduct directly - an action within Congress’ authority. Therefore, he disagreed with the majority’s view that DPPA infringed upon states’ rights and believed it should be upheld as constitutional.