McDonald v. City of Chicago

Majority reasoning

The plurality, led by Justice Alito, reasoned that under the Court's well-established incorporation framework, a Bill of Rights guarantee applies to the states if it is fundamental to the American scheme of ordered liberty and deeply rooted in the nation's history and tradition. The Court found that Heller had already established self-defense as the central component of the Second Amendment right, and that this right is deeply rooted in English and American legal history, colonial and founding-era practice, and Reconstruction-era efforts to protect freedmen's right to bear arms against Southern disarmament campaigns. The Court rejected the municipal respondents' argument that a right is fundamental only if no civilized nation could exist without it, noting this "civilized nations" test was abandoned decades ago and would call into question numerous already-incorporated rights like the exclusionary rule and Establishment Clause. The Court also directly rebutted Justice Breyer's dissent, noting there is evidence of popular consensus favoring incorporation (amicus briefs from members of Congress and 38 states), that petitioners living in high-crime, high-minority areas dispute the claim that the right doesn't protect minorities, and that incorporation always restricts state experimentation without previously stopping incorporation of other rights. Because the Court declined to revisit the narrow Slaughter-House interpretation of the Privileges or Immunities Clause, it grounded incorporation instead in the Due Process Clause, consistent with decades of "selective incorporation" precedent.

Dissent reasoning

Justice Stevens dissented, arguing that the proper inquiry is whether the specific liberty interest asserted—keeping a handgun of one's choosing in the home—is protected by the Fourteenth Amendment's own liberty guarantee, independent of mechanical "incorporation" of the Second Amendment. He contended the majority's rigid historically-focused test is unfaithful to substantive due process doctrine, which requires weighing the practical stakes, giving deference to democratic experimentation, and considering that firearms pose unique dangers to others unlike other incorporated rights. He also emphasized that the Second Amendment's militia-related purpose makes it a "federalism provision" resistant to incorporation, and that States have a long, unbroken history of extensively regulating firearms, which counsels against nationalizing an unqualified self-defense right. Justice Breyer, joined by Justices Ginsburg and Sotomayor, dissented separately, arguing that the historical case for treating private self-defense as the core of the Second Amendment is deeply disputed among historians and that history alone cannot establish the right as "fundamental." He argued that gun regulation involves complex empirical judgments about public safety that legislatures, not courts, are better equipped to make, that incorporation would work a major intrusion on state and local police power central to federalism, and that there is no political-process failure here since gun-rights supporters are a powerful, well-organized political force needing no special judicial protection.