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US v. Lopez (1995)

A quick guide to the background, decision, and impact of US v. Lopez. 

Key points

  • In 1992, Alfonso Lopez, a high school senior, walked into his San Antonio high school with a concealed weapon. He was arrested for violating a Texas law that prohibited firearm possession on school grounds. At first, Lopez was charged in a court in Texas, but he was later charged with violating the Gun-Free Schools Act, a federal offense.
  • Lopez was found guilty and appealed to the Supreme Court, arguing that this law was an overreach of congressional power because schools were supposed to be controlled at the state level, not the federal level. The court agreed with him and overturned the conviction.
  • US v. Lopez was a landmark case as ruled that the federal government had exceeded its authority under the commerce clause.

Background of the case

In McCulloch v. Maryland (1819), the Supreme Court ruled that federal laws had supremacy, or authority, over state laws. But what happens if Congress passes a law that it does not have the right to pass? Does that law still have authority over a state law? The decision in United States v. Lopez wrestled with that question.
In 1992, Alfonso Lopez walked into Edison High School in San Antonio, Texas with a .38-caliber gun. He was arrested and charged with violating a Texas law that prohibited possessing a firearm on school grounds. But the next day the charges from the state of Texas were dropped and replaced with charges from the federal government. Because federal laws have supremacy over state laws, the state charges were dismissed so that Lopez could be charged at the federal level.
The law that Lopez was charged with violating was the Gun-Free School Zones Act of 1990. Lopez was found guilty and sentenced to 6 months in prison and 2 years of probation.
Although Lopez did not dispute the fact that he had a weapon on school grounds, his lawyers argued that he should not be charged with violating a federal law since schools were under state
, not federal jurisdiction, so Congress did not have the right to pass the Gun-Free School Zones Act of 1990 in the first place.
The federal government argued that the law was within Congress’s power as it fell under the Commerce Clause of the Constitution, which gives Congress the power to regulate trade with other countries and between states.
After several appeals, the Supreme Court heard Lopez's case.

The Constitutional question at stake

Does the 1990 Gun-Free School Zones Act, forbidding individuals from knowingly carrying a gun in a school zone, violate the Constitution because it exceeds the power of Congress to legislate under the commerce clause?


Photo showing the justices of the Supreme Court in 1998.
US Supreme Court, 1998. This is a photo of the Rehnquist court (1986-2005). Image credit: Wikimedia Commons
In a 5-4 decision supporting Lopez, the Supreme Court found that the 1990 Gun-Free School Zones Act did violate the Constitution, on the grounds that Congress was overreaching its powers granted under the commerce clause.
Chief Justice William Rehnquist wrote the following about the case:
“The possession of a gun in a local school zone is in no sense an economic activity that might, through repetition elsewhere, substantially affect any sort of interstate commerce. Respondent was a local student at a local school; there is no indication that he had recently moved in interstate commerce, and there is no requirement that his possession of the firearm have any concrete tie to interstate commerce.
“To uphold the Government's contentions here, we would have to pile inference upon inference in a manner that would bid fair to convert congressional authority under the Commerce Clause to a general police power of the sort retained by the States.”
The Supreme Court found that although Congress was given the right to regulate interstate commerce, possession of a gun in a school zone was not an economic activity. It was a criminal act, but one that should be handled at the local and state level, not by the federal government. Therefore, the 1990 Gun-Free School Zones Act did violate the Constitution as it infringed on state powers.
Check your understanding
How did the decision in US v. Lopez (1995) differ from the decision in McCulloch v. Maryland (1819)?
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Why does US v. Lopez matter?

US v. Lopez preserved the system of federalism, which delegates certain powers to states and certain powers to the federal government. It upheld the principle that states have control of local issues, like gun possession on school grounds.
The case was the first in a long time that stated the federal government had overstepped its bounds and that Congress had given itself too much power under the commerce clause. United States v. Lopez reaffirmed the balance of power between the federal government and state governments.

What do you think?

Explain federalism in your own words.
What were the implications of U.S. v. Lopez for the balance of power between the federal government and state governments?

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