United States v. Alfonso Lopez, Jr. 514 U.S. 549 (1995) was the first modern US Supreme Court case to set limits to Congress's lawmaking power.
Lopez carried a handgun and bullets into his high school, Edison High, San Antonio, Texas. He was charged with violating Section 922(q) of the Gun-Free School Zones Act (1990).
The Supreme Court ruled that while Congress had broad lawmaking authority under the Commerce Clause, it was not unlimited, and did not apply to something so obviously far from commerce as carrying handguns, especially when there was no evidence that carrying them affected the economy. (A later case, United States v. Morrison, ruled that Congress could not make such laws even when there was such evidence.) The decision put an end to decades of allowing the legislature to stretch the Constitutional limits of the commerce clause. History