Second Amendment to the United States Constitution

The official text reads: "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." ¹¹¹⁶¹⁷

Several versions of the text exist, and they differ in capitalization and punctuation. The version passed by Congress differs from some of the versions ratified by the states. ¹ The handwritten original preserved in the National Archives was the version ratified by Delaware, and the Supreme Court used it in Heller. ¹ Maryland's ratified version omitted a comma. The New Jersey ratification act contained no commas. ¹

These textual differences have figured in debate over the amendment's meaning, particularly over the weight of what courts call the prefatory clause. ¹

Historical surveys often trace the amendment's roots partly to the English Bill of Rights of 1689. That document declared that Protestant subjects "may have arms for their defence suitable to their condition, and as allowed by law." ¹³ The provision grew out of conflict over the Crown's use of loyal militias to control and disarm dissidents before the Glorious Revolution replaced James II with William and Mary. ¹³

William Blackstone described the right to have arms as an auxiliary right, supporting the natural rights of self-defense and resistance to oppression. ¹

In founding-era America, local citizen militias provided for the common defense, and some people viewed standing armies of professional soldiers with suspicion. ¹³ The Declaration of Independence charged George III with keeping standing armies in peacetime without legislative consent. ¹³

Article XIII of the Pennsylvania Declaration of Rights of 1776 stated that "the people have a right to bear arms for the defence of themselves and the state." The same article warned against standing armies in peacetime. ¹³¹

Scholars disagree about how the amendment relates to earlier law. Thomas B. McAffee and Michael J. Quinlan have written that Madison "did not invent the right" but drew on a right already found in common law and in early state constitutions. ¹ Historian Jack Rakove has suggested that Madison's aim was to assure moderate Anti-Federalists that the militias would not be disarmed. ¹

Article I, Section 8 of the Constitution gave Congress power to raise armies and to provide for organizing, arming and disciplining the militia. The states kept the appointment of militia officers and the authority to train the militia. ¹ Anti-Federalists objected to this shift of military power to the federal government and pressed for a bill of rights. Federalists agreed to support amendments in order to secure ratification. ¹¹³

In Federalist No. 46, Madison wrote that a federal army could be kept in check by the militia and that state governments would be able to repel the danger of such an army. ¹

Madison's first proposal was introduced in the House on June 8, 1789. It included a clause exempting people "religiously scrupulous of bearing arms" from compelled military service. ¹ On September 4, the Senate removed a definition of the militia as "composed of the body of the people" and struck the conscientious-objector clause. ¹

On September 9, the Senate rejected a proposal to add "for the common defence" after "bear arms." It also replaced "the best" with "necessary to the." ¹ The House accepted the Senate's changes on September 21, 1789. ¹ The Bill of Rights was ratified on December 15, 1791. ¹¹²¹⁸

Law professor Carl T. Bogus has argued that the amendment was written to assure Southern states that Congress would not use its new authority over the militia to disarm state militias, which he describes as the South's principal instrument of slave control. ¹

Legal historian Paul Finkelman calls this scenario implausible. He notes that Patrick Henry and George Mason were Madison's political opponents and were not in Congress when Madison drafted the amendment. ¹ Finkelman accepts that Madison drafted an amendment to protect the states' right to maintain militias. He maintains, however, that it "had nothing to do with state police powers, which were the basis of slave patrols." ¹ Finkelman has also said that the historical record does not support the claim of a specific intent to protect the ability to suppress slave revolts. ¹

Estimates of compliance with the arms requirements of the 1792 militia law ranged from 10 to 65 percent. ¹

St. George Tucker, in an 1803 annotated edition of Blackstone, called the amendment "the true palladium of liberty." He contrasted it with English game laws that, in his view, effectively disarmed most of the English population. ¹ Joseph Story described the right as "the palladium of the liberties of a republic." He also warned that growing public indifference to militia discipline could undermine the clause's protection. ¹

In 1880, Thomas M. Cooley wrote that reading the right as guaranteed only to the militia "would be an interpretation not warranted by the intent," because the government could otherwise defeat the guarantee by not enrolling anyone. ¹

Under current federal law, the militia comprises able-bodied males aged 17 to 44 who are citizens or intend to become citizens, together with female citizens who are members of the National Guard. The law divides the militia into organized and unorganized parts. ¹

For most of its history, the Supreme Court gave the amendment little scrutiny. ¹⁹⁴ The few nineteenth-century cases treated it as a bar to federal action but not to state action. ¹⁹

In United States v. Cruikshank (1876), the Court said the amendment "has no other effect than to restrict the powers of the National Government." ¹ In United States v. Miller (1939), the Court held that the amendment did not protect weapons lacking a "reasonable relationship to the preservation or efficiency of a well regulated militia." ¹

By the start of the twenty-first century, many federal courts of appeals had concluded that the amendment protected a collective right tied to militia use. ¹⁵ In 2000, the Sixth Circuit described the lower federal courts as having uniformly held the right to be collective. ¹⁵ Another account states that every circuit decision before 2001 endorsed the collective-right model. ¹ The Fifth Circuit's 2001 decision in United States v. Emerson recognized an individual right. ¹¹⁵

In District of Columbia v. Heller (2008), the Court held after a lengthy historical analysis that the amendment protects an individual right to possess firearms for lawful purposes, including self-defense in the home. ¹⁵² The Court suggested that the right covers weapons "in common use" for lawful purposes but not "dangerous and unusual weapons." ²

The Heller majority said the right is not unlimited. It stated that nothing in its opinion cast doubt on longstanding prohibitions, such as bans on carrying firearms in sensitive places like schools and government buildings. ¹⁵ It also referred to prohibitions on possession by felons and the mentally ill. ¹ Justice Antonin Scalia said the Court had not yet undertaken a historical analysis of "the full scope of the Second Amendment." ⁵

The National Constitution Center's interpretive essay describes the Heller dissenters as reading the amendment to protect an individual right that is tied to militia service: "the right of the people of each of the several States to maintain a well-regulated militia." ³ The essay adds that the dissenters argued that, even if the amendment protected an individual right to have arms for self-defense, it should be interpreted to allow the government to ban handguns in high-crime urban areas. ³

In McDonald v. City of Chicago (2010), the Court held that the right is fundamental and is incorporated against the states through the Fourteenth Amendment. ¹⁵² The holding rested on a plurality opinion together with a separate concurrence by Justice Clarence Thomas. ¹⁵

In Caetano v. Massachusetts (2016), a brief unsigned opinion vacated a Massachusetts decision that had upheld a stun-gun ban. The Court reiterated that protected arms include bearable arms, including stun guns, that did not exist at the founding. ¹⁵²

In New York State Rifle & Pistol Association v. Bruen (2022), the Court held that the amendment's protection extends beyond the home to places of confrontation. ²

According to a Congress.gov analysis of the Court's decisions, Bruen set out a test with two parts. When the plain text covers the regulated conduct, the Constitution "presumptively protects" that conduct. To justify a regulation of that conduct, the government must then demonstrate that its law "is consistent with the Nation's historical tradition of firearm regulation." ² The government's burden under this account applies only once the plain text covers the conduct, and this description rests on that single source.

The Bruen dissenters argued that the amendment leaves states wide discretion to weigh the costs and benefits of public-carry restrictions. ³ They predicted that the majority's near-exclusive reliance on history would prove impractical given changes in society and firearms technology. ³ They also argued that the absence of a particular regulation in the past does not show that legislatures lacked the authority to enact it. ³

After Bruen, plaintiffs challenged many federal and state firearm laws, including federal bans on possession by certain categories of people. ² The Constitution Center's essay says federal courts struck down some laws that had previously been accepted as constitutional. It lists bans on firearms with obliterated serial numbers, firearms in youth summer camps, and firearms in the hands of domestic abusers, in the essay's words. ³

In United States v. Rahimi (2024), the Court voted 8–1 to reject a facial challenge to 18 U.S.C. § 922(g)(8), which bars people subject to certain domestic-violence restraining orders from possessing firearms. ²³ The majority relied on founding-era laws against going armed with dangerous and unusual weapons to terrorize the public, and on surety laws. ³ It concluded that a person who poses a clear threat of physical violence to another may be disarmed temporarily. ²³

One legal analysis states that, two years after Bruen, the Court clarified the proper application of its text-and-history test. ¹⁰ A SCOTUSblog commentary takes a different view of Rahimi's effect. It says Rahimi produced seven separate opinions and no agreement on how the historical analysis is to be done. ⁷

Justice Thomas, who wrote the Bruen opinion, dissented in Rahimi. He argued that the historical laws cited by the majority did not stop anyone from possessing or carrying a weapon for self-defense. Thomas argued that the statute strips individuals of their Second Amendment rights without requiring a criminal conviction or a history of misusing firearms. He concluded that the burdens it imposes are not remotely comparable to the historical analogues the majority cited. ³

In United States v. Hemani, the Court rejected the federal government's argument that 18 U.S.C. § 922(g)(3), which covers unlawful users of controlled substances, automatically disarms anyone who regularly uses any amount of a controlled substance regardless of individual circumstances. ²

In Rocky Mountain Gun Owners v. Polis, the Tenth Circuit held that a challenge to Colorado's ban on firearm purchases by 18-to-20-year-olds failed at Bruen's first, plain-text step. ⁸ The case is discussed in a SCOTUSblog commentary titled "How courts keep getting Bruen wrong." ⁸

A separate dispute concerns natural-law reasoning, such as Judge Matey's concurrence in Range. According to a University of Chicago Law Review critique, the concurrence presents the natural-law method as a faithful application of the Supreme Court's recent Second Amendment decisions. ⁹ The critique disputes this on three grounds. It argues that the method departs from those decisions, that its use of history is selective, and that it is too indeterminate for adjudication. ⁹ The sources available here describe the concurrence mainly through this critique and do not set out the concurrence's own rationale in detail.

In the late twentieth century, scholars debated whether the prefatory militia clause stated the amendment's only purpose or merely introduced the operative clause. ¹ This debate produced three models. The collective-right model held that the amendment protects the states' power to arm their militias. The sophisticated collective-right model recognized a limited individual right confined to members of an organized militia. The individual-right model, which some scholars termed the "standard model," recognized an individual right not dependent on militia service. ¹

Some individuals and organizations, including the National Rifle Association, have advanced what has been called an insurrectionist reading: that citizens may take up arms against a government they consider illegitimate. ¹ Congressman Jamie Raskin has argued that this view has no basis in constitutional law or scholarship. ¹ The reading is distinct from Madison's argument in Federalist No. 46 that the militia and state governments could check a federal army. ¹

Critics of Bruen argue that it assumes the absence of a historical regulation means the amendment forbids such a regulation. ⁷ They also argue that it treats divergent historical practice as if it supplied clear answers, and that confusion will persist until the historical approach is abandoned. ⁷ One such critic says Bruen confuses two questions: whether there is a Second Amendment right to possess a weapon, and whether the government is justified in infringing it. The same commentary says originalists believe history can answer the first question, while non-originalists disagree that history should determine it. ⁷ The commentary quotes Justice Ketanji Brown Jackson's observation that lower courts "have come to conflicting conclusions on virtually every consequential Second Amendment issue." ⁷

The National Constitution Center's interpretive essay describes the doctrine as "profoundly unsettled." It says the Court has not offered a consistent approach to the history-and-tradition test and that lower courts continue to issue conflicting rulings. ³

A separate question is whether the Court's decisions will last. A SCOTUSblog commentary titled "Heller and Bruen are here to stay" takes the position that they will. ⁴ The sources available here do not set out that commentary's reasoning or other defenders' detailed arguments for the history-and-tradition approach.