Prigg v. Pennsylvania

The Prigg ruling maintained that federal law held supremacy over state laws regarding fugitive slaves. It also served to weaken the ability of states to protect peoples within their boundaries and led to greater sectional conflict over slavery. Over the next 15 years it became clear the slavery question could not be resolved in the courts. In both Jones v. Van Zandt (1848) and Ableman v. Booth (1859), the Court reaffirmed the 1793 federal fugitive slave law and the property rights of slave owners. The Court maintained its role was to uphold the laws and that the moral question of slavery was "a political question, settled by each state for itself . . . and which we possess no authority as a judicial body to modify or overrule."

The primary legal question addressed by Prigg was the separate rights of states and Congress to regulate certain activities. Though the Court affirmed the supremacy of federal law in several cases in the early 1840s, an era of limited federal government, however, continued until 1932 with the beginnings of New Deal programs during the depression. The judicial doctrine of "preemption" in which Congress could enact laws that took precedence over existing state laws on the same subject was soon established further clarifying the supremacy of federal government. In the Hines v. Davidowitz (1941) case, the Court ruled that federal law regulating the registration of aliens preempted state law. By the 1960s regulatory laws were increasingly passed by both Congress and the states making preemption legal cases more frequent. An example was the Voting Rights Act of 1965 in which a federal law preempted state laws by imposing consistent national anti-discrimination standards.

After decades of increasing centralized power held by the federal government, in the mid-1980s the Court began to roll back federal supremacy. This trend towards states' rights was further fueled by the 1994 election of a Republican-controlled Congress that campaigned against centralized government. A key target was the Commerce Clause of the Constitution giving Congress power to regulate matters involving the national economy. In United States v. Lopez (1995) the Court ruled that the Commerce Clause did not give Congress power to ban guns near schools as the government argued. The ruling was the first in six decades to hold that Congress could not regulate a private activity under the Commerce Clause. Despite this increased support for states' rights in the 1990s, several factors led to increased efforts at federal preemptions including the explosion in telecommunications technology. Increased electronic commerce, including Internet shopping and banking, posed major threats to state sales tax schemes and traditional state regulation of banks. Again, the debate over states' rights versus centralized federal government control erupted as it had over two centuries ago with the Hamilton-Madison debates.