On May 15, the Supreme Court called for the views of the United States’ Solicitor General on Rinehart v. California, a challenge to California’s ban on suction dredge mining. The case raises important questions about federalism, preemption, and state regulation of federal lands.

In 2009, California adopted a blanket ban against suction dredge mining through the state, including on federal property. An individual named Brandon Rinehart challenged the ban as conflicting with the federal Mining Law of 1872, which declared that federal lands are “free and open” to mining. The California Supreme Court disagreed and upheld Rinehart’s conviction for violating the ban.

The United States Supreme Court has recognized that states may regulate the environmental impacts of mining, but they may not simply ban the activity in lieu of regulating it. In upholding the ban, the California Supreme Court’s opinion is at odds with that principle, and with decisions of the Eighth Circuit, Federal Circuit, and the Colorado Supreme Court, each of which held that states may control mining but cannot completely prohibit it.

In effect, the California Supreme Court denied that the 1872 Mining Law has any preemptive force, even where, as here, a state law is irreconcilable with the federal law’s stated purpose. But the Supreme Court has repeatedly held that state legislation which frustrates the full effectiveness of federal law is invalid. In other words, states lack authority to create obstacles to the accomplishment and execution of the full purposes and objectives of Congress’ laws.

The Supreme Court’s request for the Solicitor General’s views is noteworthy because the Court grants cases backed by the Solicitor General’s recommendation at a much higher rate than is typical. And the only time the United States has taken a position on this issue in the Supreme Court it argued that the Mining Law broadly preempts any state regulation of mining on federal lands. So one may expect the federal government to argue that the ban is invalid.