List of landmark court decisions in the United States

For a list of landmark court decisions in other countries, see Lists of landmark court decisions.

The following is a partial list of landmark court decisions in the United States. Landmark decisions establish a significant new legal principle or concept or otherwise substantially change the interpretation of existing law. Such a decision may settle the law in more than one way:

• distinguishing a new principle that refines a prior principle, thus departing from prior practice without violating the rule of stare decisis;
• establishing a “test” or a measurable standard that can be applied by courts in future decisions.

In the United States, landmark court decisions come most frequently from the Supreme Court. United States courts of appeals may also make such decisions, particularly if the Supreme Court chooses not to review the case or if it adopts the holding of the lower court. Although many cases from state supreme courts are significant in developing the law of that state, only a few are so revolutionary that they announce standards that many other state courts then choose to follow.

Individual rights

Discrimination based on race

• Dred Scott v. Sandford, 60 U.S. 393 (1857) People of African descent that are slaves or were slaves and subsequently freed, along with their descendants, cannot be United States citizens. Consequently, they cannot sue in federal court. Also, slavery cannot be outlawed in the western territories before they access statehood. After the Civil War, this decision was voided by the Thirteenth and Fourteenth Amendments to the Constitution.
• Civil Rights Cases, 109 U.S. 3 (1883) Neither the Thirteenth nor the Fourteenth Amendment empower Congress to safeguard blacks against the actions of private individuals.
• Plessy v. Ferguson, 163 U.S. 537 (1896) Segregated facilities for blacks and whites are constitutional under the doctrine of separate but equal, which held for close to 60 years. (Overruled by Brown v. Board of Education (1954))
• Korematsu v. United States, 323 U.S. 214 (1944) President Franklin D. Roosevelt's Executive Order 9066 is constitutional; therefore, American citizens of Japanese descent can be interned and deprived of their basic constitutional rights. This case featured the first application of strict scrutiny to racial discrimination by the government.
• Smith v. Allwright, 321 U.S. 649 (1944) Primary elections must be open to voters of all races.
• Morgan v. Virginia, 328 U.S. 373 (1946) Virginia's state law enforcing segregation on interstate buses is unconstitutional.
• Shelley v. Kraemer, 334 U.S. 1 (1948) Courts may not enforce racial covenants on real estate.
• Henderson v. United States, 339 U.S. 816 (1950) The Interstate Commerce Act of 1887 makes it unlawful for a railroad that engages in interstate commerce to subject any particular person to any undue or unreasonable prejudice or disadvantage in any respect whatsoever.
• Brown v. Board of Education, 347 U.S. 483 (1954) Segregated schools in the several states are unconstitutional in violation of the Fourteenth Amendment. The Court found that the separate but equal doctrine adopted in Plessy v. Ferguson (1896) "has no place in the field of public education."
• Bolling v. Sharpe, 347 U.S. 497 (1954) Segregated schools in the District of Columbia violate the Fifth Amendment. This case is the companion case to Brown.
• Sarah Keys v. Carolina Coach Company, 64 MCC 769 (1955) According to the Interstate Commerce Commission, the non-discrimination language of the Interstate Commerce Act of 1887 bans the segregation of black passengers on buses traveling across state lines. The Supreme Court adopted and expanded this decision in Boynton v. Virginia (1960).
• Browder v. Gayle, 142 F. Supp. 707 (M.D. Ala. 1956) Bus segregation is unconstitutional under the Fourteenth Amendment's Equal Protection Clause.
• Boynton v. Virginia, 364 U.S. 454 (1960) Racial segregation in all forms of public transportation is illegal under the Interstate Commerce Act of 1887.
• Loving v. Virginia, 388 U.S. 1 (1967) Laws that prohibit interracial marriage (anti-miscegenation laws) are unconstitutional.
• Jones v. Alfred H. Mayer Co., 392 U.S. 409 (1968) The federal government may prohibit discrimination in housing by private parties under the Civil Rights Act of 1968.
• Gates v. Collier, 501 F. 2d 1291 (5th Cir. 1974) This decision brought an end to the trustee system and flagrant inmate abuse at the Mississippi State Penitentiary in Parchman, Mississippi. It was the first body of law developed in the Fifth Circuit that held that a variety of forms of corporal punishment against prisoners is considered cruel and unusual punishment and that abolished racial segregation in prisons.
• Regents of the University of California v. Bakke, 438 U.S. 265 (1978) Race-based set-asides in educational opportunities violate the Equal Protection Clause of the Fourteenth Amendment. This decision leaves the door open for some use of race in admission decisions.
• Adarand Constructors, Inc. v. Peña, 515 U.S. 200 (1995) Race-based discrimination, including discrimination in favor of minorities (affirmative action), is subject to strict scrutiny.
• Grutter v. Bollinger, 539 U.S. 306 (2003) A narrowly-tailored use of race in student admission decisions may be permissible under the Fourteenth Amendment's Equal Protection Clause because a diverse student body is beneficial to all students. This was hinted at in Regents v. Bakke (1978).

Discrimination based on sex

• Muller v. Oregon, 208 U.S. 412 (1908) Oregon's restrictions on the working hours of women are constitutional.
• Phillips v. Martin Marietta Corp., 400 U.S. 542 (1971) An employer may not, in the absence of business necessity, refuse to hire women with preschool-age children while hiring men with such children.
• Reed v. Reed, 404 U.S. 71 (1971) Administrators of estates cannot be named in a way that discriminates on the basis of sex.
• Frontiero v. Richardson, 411 U.S. 677 (1973) Sex-based discriminations are inherently suspect. A statute giving benefits to the spouses of male, but not female members of the uniformed services (on the assumption that only the former are dependent) is unconstitutional.
• Craig v. Boren, 429 U.S. 190 (1976) Setting different minimum ages for females (18) and males (21) to be allowed to buy beer is unconstitutional sex-based discrimination contrary to the Equal Protection Clause.
• United States v. Virginia, 518 U.S. 515 (1996) Sex-based "separate but equal" military training facilities violate the Fourteenth Amendment's Equal Protection Clause.

Discrimination based on sexual orientation

• Bowers v. Hardwick, 478 U.S. 186 (1986) A Georgia law that defines certain acts of private sexual conduct between homosexual persons as a crime does not violate the Fourteenth Amendment. (Overruled by Lawrence v. Texas (2003))
• Romer v. Evans, 517 U.S. 620 (1996) A Colorado state constitutional amendment that disqualifies homosexuals from obtaining protections under the law is a violation of the Fourteenth Amendment's Equal Protection Clause.
• Lawrence v. Texas, 539 U.S. 558 (2003) A Texas law criminalizing adults who engage in consensual same-sex sexual conduct furthers no legitimate state interest and violates their right to privacy under the Fourteenth Amendment's Due Process Clause. This decision effectively nullifies all sodomy laws in the United States.
• United States v. Windsor, 570 U.S. ___ (2013) Section 3 of the Defense of Marriage Act, which defines—for federal law purposes—the terms "marriage" and "spouse" to apply only to marriages between one man and one woman, is a deprivation of the equal liberty of the person protected by the Fifth Amendment's Due Process Clause. The federal government must recognize same-sex marriages that have been approved by the states.

Birth control and abortion

• Griswold v. Connecticut, 381 U.S. 479 (1965) A Connecticut law that criminalizes the use of contraception by married couples is unconstitutional because all Americans have a constitutionally protected right to privacy.
• Eisenstadt v. Baird, 405 U.S. 438 (1972) A Massachusetts law that criminalizes the use of contraception by unmarried couples violates the right to privacy established in Griswold as well as the Equal Protection Clause of the Fourteenth Amendment.
• Roe v. Wade, 410 U.S. 113 (1973) Laws that restrict a woman's ability to have an abortion prior to viability are unconstitutional. Most restrictions during the first trimester are prohibited, and only health-related restrictions are permitted during the second trimester.
• Carey v. Population Services International, 431 U.S. 678 (1977) Laws that restrict the sale, distribution, and advertisement of contraceptives to both adults and minors are unconstitutional.
• Planned Parenthood of Southeastern Pennsylvania v. Casey, 505 U.S. 833 (1992) A woman is still able to have an abortion before viability, but several restrictions are now permitted during the first trimester. The strict trimester framework of Roe is discarded and replaced with the more vague "undue burden" test.
• Stenberg v. Carhart, 530 U.S. 914 (2000) Laws that ban partial-birth abortion are unconstitutional if they do not make an exception for the woman's health or if they cannot be reasonably construed to apply only to the partial-birth abortion procedure and not to other abortion methods.
• Gonzales v. Carhart, 550 U.S. 124 (2007) Congress can prohibit a specific abortion procedure, in this case intact dilation and extraction, which is also known as partial-birth abortion, on the grounds that it "implicates additional ethical and moral concerns that justify a special prohibition."

End of life

• Cruzan v. Director, Missouri Department of Health, 497 U.S. 261 (1990) When a family has requested the termination of life-sustaining treatments for their vegetative relative, the state may constitutionally oppose this request if there is a lack of evidence of a clear earlier wish by said relative.
• Washington v. Glucksberg, 521 U.S. 702 (1997) Washington's prohibition on assisted suicide is constitutional.
• Vacco v. Quill, 521 U.S. 793 (1997) New York's prohibition on assisted suicide does not violate the Equal Protection Clause.
• Gonzales v. Oregon, 546 U.S. 243 (2006) The Controlled Substances Act does not prevent physicians from prescribing drugs for the assisted suicide of the terminally ill under state law.

Restrictions on involuntary commitment

• O'Connor v. Donaldson, 422 U.S. 563 (1975) States cannot involuntarily commit individuals if they are not a danger to themselves or others and are capable of living by themselves or with the aid of responsible family members or friends.

Power of Congress to enforce civil rights

• Heart of Atlanta Motel, Inc. v. United States, 379 U.S. 241 (1964) The Civil Rights Act of 1964 applies to places of public accommodation patronized by interstate travelers by reason of the Commerce Clause.
• Katzenbach v. McClung, 379 U.S. 294 (1964) The power of Congress to regulate interstate commerce extends to a restaurant not patronized by interstate travelers, but which serves food that has moved in interstate commerce. This ruling makes the Civil Rights Act of 1964 apply to virtually all businesses.
• City of Boerne v. Flores, 521 U.S. 507 (1997) Section 5 of the Fourteenth Amendment does not permit Congress to substantially increase the scope of the rights determined by the judiciary. Congress may only enact remedial or preventative measures that are consistent with the Fourteenth Amendment interpretations of the Supreme Court.

Other areas

• Corfield v. Coryell, 6 Fed. Cas. 546 (C.C.E.D. Pa. 1823) Some of the rights protected by the Privileges and Immunities Clause include the freedom of movement through the states, the right of access to the courts, the right to purchase and hold property, an exemption from higher taxes than those paid by state residents, and the right to vote.
• Crandall v. Nevada, 73 U.S. 35 (1868) The freedom of movement is a fundamental right; a state cannot inhibit people from leaving the state by taxing them.
• United States v. Wheeler, 254 U.S. 281 (1920) The Constitution grants to states, not the federal government, the power to prosecute individuals for wrongful interference with the right to travel.
• Reid v. Covert, 354 U.S. 1 (1957) United States citizens abroad, even when associated with the military, cannot be deprived of the protections of the Constitution and cannot be made subject to military jurisdiction.
• United States v. Guest, 383 U.S. 745 (1966) There is constitutional right to travel from state to state and the protection of the 14th Amendment extends to citizens who suffer rights deprivations at the hands of private conspiracies, where there is minimal state participation in the conspiracy.

Criminal law

Freedom from unreasonable searches and seizures

• Mapp v. Ohio, 367 U.S. 643 (1961) Evidence that is obtained in violation of the Fourth Amendment is inadmissible in state court.
• Katz v. United States, 389 U.S. 347 (1967) The Fourth Amendment's ban on unreasonable searches and seizures applies to all places where an individual has a "reasonable expectation of privacy".
• United States v. United States District Court for the Eastern District of Michigan, 407 U.S. 297 (1972) Government officials must obtain a warrant before beginning electronic surveillance even if domestic security issues are involved. The "inherent vagueness of the domestic security concept" and the potential for abusing it to quell political dissent make the Fourth Amendment's protections especially important when the government engages in spying on its own citizens.
• New Jersey v. T. L. O., 469 U.S. 325 (1985) The Fourth Amendment's ban on unreasonable searches applies to those conducted by public school officials as well as those conducted by law enforcement personnel, but public school officials can use the less strict standard of reasonable suspicion instead of probable cause.
• Vernonia School District 47J v. Acton, 515 U.S. 646 (1995) Schools may implement random drug testing upon students participating in school-sponsored athletics.
• Board of Education v. Earls, 536 U.S. 822 (2002) Coercive drug testing imposed by school districts upon students who participate in extracurricular activities does not violate the Fourth Amendment.
• Georgia v. Randolph, 547 U.S. 103 (2006) Police cannot conduct a warrantless search in a home where one occupant consents and the other objects.
• In re Directives, (2008) According to the United States Foreign Intelligence Surveillance Court of Review, an exception to the Fourth Amendment’s warrant requirement exists when surveillance is conducted to obtain foreign intelligence for national security purposes and is directed against foreign powers or agents of foreign powers reasonably believed to be located outside the United States.
• United States v. Jones, 565 U.S. ___ (2012) Attaching a GPS device to a vehicle and then using the device to monitor the vehicle’s movements constitutes a search under the Fourth Amendment.

Right to an attorney

• Glasser v. United States, 315 U.S. 60 (1942) A defense lawyer's conflict of interest arising from a simultaneous representation of codefendants violates the Assistance of Counsel Clause of the Sixth Amendment.
• Betts v. Brady, 316 U.S. 455 (1942) Indigent defendants may be denied counsel when prosecuted by a state. (Overruled by Gideon v. Wainwright (1963))
• Gideon v. Wainwright, 372 U.S. 335 (1963) All defendants have the right to an attorney and must be provided one by the state if they are unable to afford legal counsel.
• Escobedo v. Illinois, 378 U.S. 478 (1964) A person in police custody has the right to speak to an attorney.
• Miranda v. Arizona, 384 U.S. 436 (1966) Police must advise criminal suspects of their rights under the Constitution to remain silent, to consult with a lawyer, and to have one appointed to them if they are indigent. A police interrogation must stop if the suspect states that he or she wishes to remain silent.
• In re Gault, 387 U.S. 1 (1967) Juvenile defendants are protected under the Due Process Clause of the Fourteenth Amendment.
• Michigan v. Jackson, 475 U.S. 625 (1986) If a police interrogation begins after a defendant asserts his or her right to counsel at an arraignment or similar proceeding, then any waiver of that right for that police-initiated interrogation is invalid. (Overruled by Montejo v. Louisiana (2009))
• Montejo v. Louisiana, 556 U.S. 778 (2009) A defendant may waive his or her right to counsel during a police interrogation even if the interrogation begins after the defendant's assertion of his or her right to counsel at an arraignment or similar proceeding.

Other rights regarding counsel

• Strickland v. Washington, 466 U.S. 668 (1984) To obtain relief due to ineffective assistance of counsel, a criminal defendant must show that counsel's performance fell below an objective standard of reasonableness and that counsel's deficient performance gives rise to a reasonable probability that, if counsel had performed adequately, the result of the proceeding would have been different.
• Padilla v. Kentucky, 559 U.S. 356 (2010) Criminal defense attorneys are duty-bound to inform clients of the risk of deportation under three circumstances. First, where the law is unambiguous, attorneys must advise their criminal clients that deportation "will" result from a conviction. Second, where the immigration consequences of a conviction are unclear or uncertain, attorneys must advise that deportation "may" result. Finally, attorneys must give their clients some advice about deportation—counsel cannot remain silent about immigration consequences.

Right to remain silent

• Berghuis v. Thompkins, 560 U.S. ___ (2010) The right to remain silent does not exist unless a suspect invokes it unambiguously.
• Salinas v. Texas, 570 U.S. ___ (2013) The Fifth Amendment's protection against self-incrimination does not protect an individual's refusal to answer questions asked by law enforcement before this individual has been arrested or given the Miranda warning. A witness cannot invoke the privilege by simply standing mute. Instead it must be expressly invoked by the witness.

Competence

• Dusky v. United States, 362 U.S. 402 (1960) A defendant has the right to a competency evaluation before proceeding to trial.
• Rogers v. Okin, 478 F. Supp. 1342 (D. Mass. 1979) The competence of a committed patient is presumed until he or she is adjudicated incompetent.
• Ford v. Wainwright, 477 U.S. 399 (1986) A defendant has the right to a competency evaluation before being executed.
• Godinez v. Moran, 509 U.S. 389 (1993) A defendant who is competent to stand trial is automatically competent to plead guilty or waive the right to legal counsel.

Capital punishment

• Furman v. Georgia, 408 U.S. 238 (1972) The arbitrary and inconsistent imposition of the death penalty violates the Eighth and Fourteenth Amendments and constitutes cruel and unusual punishment. This decision initiates a nationwide de facto moratorium on executions that lasts until the Supreme Court's decision in Gregg v. Georgia (1976).
• Jurek v. Texas, 428 U.S. 262 (1976) A "three-pronged" test for determining if the death penalty should be imposed is constitutional.
• Woodson v. North Carolina, 428 U.S. 280 (1976) North Carolina's mandatory death sentence statute violates the Eighth and Fourteenth Amendments.
• Gregg v. Georgia, 428 U.S. 153 (1976) Carefully drafted death penalty statutes may be constitutional. This ruling made executions possible again after Furman v. Georgia (see above) had stopped them.
• Proffitt v. Florida, 428 U.S. 242 (1976) Requirement of comparison of mitigating to aggravating factors to be used to impose death sentence is constitutional.
• Roberts v. Louisiana, 428 U.S. 325 (1976) Mandatory death sentences are unconstitutional.
• Coker v. Georgia, 433 U.S. 584 (1977) A sentence of death may not be imposed for the crime of rape.
• Enmund v. Florida, 458 U.S. 782 (1982) A sentence of death may not be imposed on offenders who are involved in a felony during which a murder is committed but who do not actually kill, attempt to kill, or intend that a killing take place.
• Ford v. Wainwright, 477 U.S. 399 (1986) A sentence of death may not be imposed on the insane.
• Atkins v. Virginia, 536 U.S. 304 (2002) A sentence of death may not be imposed on mentally retarded offenders, but the states can define what it means to be mentally retarded.
• Roper v. Simmons, 543 U.S. 551 (2005) A sentence of death may not be imposed on juvenile offenders.
• Kennedy v. Louisiana, 554 U.S. 407 (2008) The death penalty is unconstitutional in all cases that do not involve murder or crimes against the State.

Other criminal sentences

• Graham v. Florida, 560 U.S. ___ (2010) A sentence of life imprisonment without the possibility of parole may not be imposed on juvenile non-homicide offenders.
• Miller v. Alabama, 567 U.S. ___ (2012) A sentence of life imprisonment without the possibility of parole may not be a mandatory sentence for juvenile offenders.

Federalism

• Chisholm v. Georgia, 2 U.S. 419 (1793) The Constitution prevents the states from exercising sovereign immunity. Therefore, the states can be sued in federal court by citizens of other states. This decision was voided by the Eleventh Amendment in 1795, just two years after it was handed down.
• Hylton v. United States, 3 U.S. 171 (1796) A tax on the possession of goods is not a direct tax that must be apportioned among the states according to their populations. This case featured the first example of judicial review by the Supreme Court.
• Ware v. Hylton, 3 U.S. 199 (1796) A section of the Treaty of Paris supersedes an otherwise valid Virginia statute under the Supremacy Clause. This case featured the first example of judicial nullification of a state law.
• Marbury v. Madison, 5 U.S. 137 (1803) Section 13 of the Judiciary Act of 1789 is unconstitutional because it attempts to expand the original jurisdiction of the Supreme Court beyond that permitted by the Constitution. Congress cannot pass laws that contradict the Constitution. This case featured the first example of judicial nullification of a federal law.
• Martin v. Hunter's Lessee, 14 U.S. 304 (1816) Federal courts may review State court decisions when they rest on federal law or the federal constitution. This decision provides for the uniform interpretation of federal law throughout the various states.
• McCulloch v. Maryland, 17 U.S. 316 (1819) The court stated the doctrine of implied powers, from the Necessary and Proper Clause at Article I, section 8. To fulfill its goal, the federal government may use any means the constitution does not forbid (as opposed to only what the constitution explicitly allow or only what can be proved to be necessary). State government may in no way hinder the legitimate action of the federal government like the state Maryland did in this case by levying a tax on the Bank of the United States.
• Gibbons v. Ogden, 22 U.S. 1 (1824) The power to regulate interstate navigation is granted to Congress by the Commerce Clause of the Constitution.
• Cooley v. Board of Wardens, 53 U.S. 299 (1852) When local circumstances make it necessary the states can regulate interstate commerce, providing that such regulations do not conflict with federal law. States' laws related to commerce powers can be valid so long as Congress is silent on the matter.
• Ableman v. Booth, 62 U.S. 506 (1859) State courts cannot issue rulings that contradict the decisions of federal courts.
• Texas v. White, 74 U.S. 700 (1869) The states that formed the Confederate States of America during the Civil War never actually left the Union because a state cannot unilaterally secede from the United States.
• Swift & Co. v. United States, 196 U.S. 375 (1905) Congress could constitutionally prohibit local business practices as a means to regulate interstate commerce because those practices, when combined together, were within "the stream of commerce" between the states.
• Missouri v. Holland, 252 U.S. 416 (1920) Treaties made by the federal government are supreme over any state concerns about such treaties having abrogated any states' rights arising under the Tenth Amendment.
• United States v. Wheeler, 254 U.S. 281 (1920) The Constitution grants to states, not the federal government, the power to prosecute individuals for wrongful interference with the right to travel.
• National Labor Relations Board v. Jones & Laughlin Steel Corporation, 301 U.S. 1 (1937) Confirmed the constitutionality of the National Labor Relations Act, which created the National Labor Relations Board. Ruled that the Commerce Clause applies to labor relations; therefore, the NLRB has the right to sanction companies that fire or discriminate against workers for belonging to a union. The court also ovrruled Swift & Co. v. United States (1905) by holding that a local commercial activity considered in isolation may still constitute "interstate commerce" if that activity has a "close and substantial relationship" to interstate commerce.
• Steward Machine Company v. Davis, 301 U.S. 548 (1937) The federal government is permitted to impose a tax, even if the goal of the tax is not simply the collection of revenue (in this case, it was argued that a tax upon employers was designed to coerce states into adopting laws providing unemployment compensation).
• United States v. Darby Lumber Co., 312 U.S. 100 (1941) Control over interstate commerce belongs entirely to Congress. The Fair Labor Standards Act of 1938 is constitutional under the Commerce Clause because it prevents the states from lowering labor standards to gain commercial advantages.
• Wickard v. Filburn, 317 U.S. 111 (1942) The Commerce Clause of the constitution allows Congress to regulate anything that has a substantial economic effect on commerce, even if that effect is indirect.
• Cooper v. Aaron, 358 U.S. 1 (1958) The states are bound by the decisions of the Supreme Court and cannot choose to ignore them.
• United States v. Nixon, 418 U.S. 683 (1974) The doctrine of executive privilege is legitimate; however, the President cannot invoke it in criminal cases to withhold evidence.
• South Dakota v. Dole, 483 U.S. 203 (1987) Congress may attach reasonable conditions to funds disbursed to the states without violating the Tenth Amendment.
• U.S. Term Limits, Inc. v. Thornton, 514 U.S. 779 (1995) State law cannot set term limits on members of Congress.
• United States v. Lopez, 514 U.S. 549 (1995) The Gun-Free School Zones Act of 1990 is unconstitutional. The Commerce Clause of the Constitution does not give Congress the power to prohibit the mere possession of a gun near a school because gun possession by itself is not an economic activity that affects interstate commerce even indirectly.
• Clinton v. Jones, 520 U.S. 681 (1997) The President of the United States has no particular immunity, which could require civil law litigation against the President for a dispute unrelated to the office of President (e.g. having occurred before (s) he took office), to be stayed until the end of the President's term. Such delay would deprive plaintiffs, (and arguably the defendant), of the Sixth Amendment right to a speedy trial.
• Printz v. United States, 521 U.S. 898 (1997) The interim provision of the Brady Handgun Violence Prevention Act that requires state and local officials to conduct background checks on firearm purchasers violates the Tenth Amendment.
• Clinton v. City of New York, 524 U.S. 417 (1998) The Line Item Veto Act of 1996 is unconstitutional because it allows the President to amend or repeal parts of statutes without the pre-approval of Congress. According to the Presentment Clause of the Constitution, Congress must initiate all changes to existing laws.
• United States v. Morrison, 529 U.S. 598 (2000) The section of the Violence Against Women Act of 1994 that gives victims of gender-motivated violence the right to sue their attackers in federal court is an unconstitutional intrusion on states' rights.
• Gonzales v. Raich, 545 U.S. 1 (2005) Congress may ban the use of marijuana even in states that have approved its use for medicinal purposes.
• National Federation of Independent Business v. Sebelius, 567 U.S. ___ (2012) The Patient Protection and Affordable Care Act's expansion of Medicaid is unconstitutional as-written—it is unduly coercive to force the states to choose between participating in the expansion or forgoing all Medicaid funds. In addition, the individual health insurance mandate is constitutional by virtue of the Taxing and Spending Clause (though not by the Commerce Clause or the Necessary and Proper Clause).

First Amendment rights

Freedom of speech and of the press

• Schenck v. United States, 249 U.S. 47 (1919) Established the idea that "clear and present danger" in certain speech is not protected by the First Amendment. Schenck's attempts to obstruct recruitment processes were perceived as a "clear and present danger that will bring about the substantive evils that Congress has a right to prevent".
• Near v. Minnesota, 283 U.S. 697 (1931) Recognized the freedom of the press by rejecting prior restraints on publication. Except in rare cases, censorship is unconstitutional.
• Stromberg v. California, 283 U.S. 359 (1931) Symbolic speech or "expressive conduct" covered by the First Amendment is protected from state infringement by the Fourteenth Amendment.
• Chaplinsky v. New Hampshire, 315 U.S. 568 (1942) Established the "fighting words doctrine" that some words are not protected under the First Amendment because they are tantamount to violent actions.
• Joseph Burstyn, Inc. v. Wilson, 342 U.S. 495 (1952) Motion pictures, as a form of artistic expression, are protected by the First Amendment. This decision overruled Mutual Film Corporation v. Industrial Commission of Ohio, 236 U.S. 230 (1915).
• Roth v. United States (and Alberts v. California), 354 U.S. 476 (1957) Obscene material is not protected by the First Amendment.
• One, Inc. v. Olesen, 355 U.S. 371 (1958) Pro-homosexual writing is not per se obscene.
• New York Times Co. v. Sullivan (and Abernathy v. Sullivan), 376 U.S. 254 (1964) Public officials, to prove they were libelled, must show not only that a statement is false, but also that it has been published with malicious intent.
• Curtis Publishing Co. v. Butts, 388 U.S. 130 (1967) While news organizations are protected from liability when printing allegations about public officials under New York Times Co. v. Sullivan, they may still be liable to public figures if the information they disseminate is recklessly gathered and unchecked.
• Brandenburg v. Ohio, 395 U.S. 444 (1969) Mere advocacy of the use of force, or of violation of law (in this case, by a Ku Klux Klan leader) is protected by the First Amendment free speech clause. Only inciting others to take direct and immediate unlawful action would be without constitutional protection.
• Tinker v. Des Moines Independent Community School District, 393 U.S. 503 (1969) Wearing armbands as a form of protest on public school grounds is protected by the First Amendment.
• Cohen v. California, 403 U.S. 15 (1971) One should not be convicted for wearing a jacket in a courtroom emblazoned with the phrase "Fuck the Draft" (in the Vietnam War context), as this is communication, protected by the free speech clause of the 1st Amendment. The word "fuck" itself, clearly not directed at the hearer, is not in this particular instance a fighting word, and so not without constitutional protection.
• New York Times Co. v. United States, 403 U.S. 713 (1971) The federal government's desire to keep the Pentagon Papers classified is not strong enough to justify a violation of the First Amendment.
• Miller v. California, 413 U.S. 15 (1973) To be obscene, a work must fail several tests to determine its value to society, essentially having "no redeeming social value" to be so declared.
• Gertz v. Robert Welch, Inc., 418 U.S. 323 (1974) The state interest in compensating injury to the reputation of private individuals is greater than for public officials and public figures, for private individuals are more vulnerable to injury from defamation, ecause private individuals have less effective opportunities for rebuttal than do public officials and public figures. States can define for themselves the appropriate standard of liability for a publisher or broadcaster of defamatory falsehood injuries to a private individual and states may constitutionally allow private individuals to recover damages for defamation on the basis of any standard of care except liability without fault. The First Amendment requires only a “negligence standard for private defamation actions.”
• Buckley v. Valeo, 424 U.S. 1 (1976) Spending money to influence elections is a form of constitutionally protected free speech.
• Federal Communications Commission v. Pacifica Foundation, 438 U.S. 726 (1978) Defined the power of the FCC to regulate indecent broadcasts, including the so-called "seven dirty words" that could then not be said on TV or radio.
• Bethel School District v. Fraser, 478 U.S. 675 (1986) The First Amendment, as applied through the Fourteenth, permits a public school to punish a student for giving a lewd and indecent, but not obscene, speech at a school assembly.
• Hazelwood v. Kuhlmeier, 484 U.S. 260 (1988) Public school curricular student newspapers that have not been established as forums for student expression are subject to a lower level of First Amendment protection than independent student expression or newspapers established (by policy or practice) as forums for student expression.
• Hustler Magazine v. Falwell, 485 U.S. 46 (1988) Parodies of public figures, including those intended to cause emotional distress, are protected by the First Amendment.
• Texas v. Johnson, 491 U.S. 397 (1989) Law prohibiting burning of the American flag is unconstitutional as violating the First Amendment.
• Reno v. American Civil Liberties Union, 521 U.S. 844 (1997) The Communications Decency Act, regulating certain content on the Internet, is so overbroad as to be an unconstitutional restraint on the First Amendment.
• Citizens United v. Federal Election Commission, 558 U.S. 310 (2010) Limits on corporate and union political expenditures during an election cycle violate the First Amendment. Corporations and labor unions can spend unlimited sums in support of or in opposition to candidates, as long as the spending is independent of the candidates.
• Snyder v. Phelps, 562 U.S. ___ (2011) The infamous Westboro Baptist Church's picketing of military funerals cannot be liable for a tort of emotional distress.
• Brown v. Entertainment Merchants Association, 564 U.S. ___ (2011) Video games are a distinct communications medium protected by the First Amendment.

Freedom of religion

• Reynolds v. United States, 98 U.S. 145 (1879) Religious belief or duty cannot be used as a defense against a criminal indictment.
• Davis v. Beason, 133 U.S. 333 (1890) The Edmunds Anti-Polygamy Act of 1882 does not violate the Free Exercise Clause of the First Amendment even though polygamy is part of several religious beliefs.
• Cantwell v. Connecticut, 310 U.S. 296 (1940) Free exercise of religion is protected from intrusive state action through the Due Process Clause of the Fourteenth Amendment.
• Minersville School District v. Gobitis, 310 U.S. 586 (1940) Public schools can compel students to salute the American Flag and recite the Pledge of Allegiance despite the students' religious objections to these practices. Later overruled in West Virginia State Board of Education v. Barnette, 319 U.S. 624 (1943).
• Murdock v. Pennsylvania, 319 U.S. 105 (1943) A Pennsylvania ordinance imposing a license tax for those selling merchandise when such material is religious in nature violates the Free Exercise clause.
• Everson v. Board of Education, 330 U.S. 1 (1947) Government reimbursing transportation costs to and from Catholic schools does not violate the Establishment Clause of the First Amendment; however, a wall of separation must be erected between church and state.
• McCollum v. Board of Education, 333 U.S. 203 (1948) The use of public school facilities by religious organizations to give religious instruction to school children violates the Establishment Clause of the First Amendment.
• Engel v. Vitale, 370 U.S. 421 (1962) Government-directed prayer in public schools, even if it is denominationally neutral and non-mandatory, violates the Establishment Clause of the First Amendment.
• Abington School District v. Schempp (and Murray v. Curlett), 374 U.S. 203 (1963) The Establishment Clause of the First Amendment forbids state mandated reading of the Bible, or recitation of the Lord's Prayer in public schools.
• Lemon v. Kurtzman, 403 U.S. 602 (1971) For a law to be considered constitutional under the Establishment Clause of the First Amendment, the law must have a legitimate secular purpose, must not have the primary effect of either advancing or inhibiting religion, and must not result in an excessive entanglement of government and religion.
• Wisconsin v. Yoder, 406 U.S. 205 (1972) Parents may remove children from public school for religious reasons.
• Edwards v. Aguillard, 482 U.S. 578 (1987) Teaching creationism in public schools is unconstitutional.
• Employment Division v. Smith, 494 U.S. 872 (1990) Neutral laws of general applicability do not violate the Free Exercise Clause of the First Amendment.
• Lee v. Weisman, 505 U.S. 577 (1992) Public schools inviting clergy to read prayer at an official ceremony (here a graduation ceremony) violates First Amendment non-establishment clause.
• Church of Lukumi Babalu Aye v. City of Hialeah, 508 U.S. 520 (1993) Government must show a compelling interest to draw a statute targeting a religion's ritual (as opposed to a statute that happens to burden the ritual, but is not directed at it). Failing to show such an interest, the prohibition of animal sacrifice is a violation of First Amendment free exercise clause.
• Rosenberger v. University of Virginia, 515 U.S. 819 (1995) A university cannot fund secular groups using student dues but exclude religious groups that qualify under the same funding scheme.
• Agostini v. Felton, 521 U.S. 203 (1997) A government program sending government employees to parochial schools (and also, to other private schools) specifically to provide remedial education to disadvantaged children (and not to all children) does not violate the First Amendment non establishment clause.
• Santa Fe Independent School Dist. v. Doe, 530 U.S. 290 (2000) A Texas public school district’s policy of having students vote on a prayer to be read by a student at football games violated the Establishment Clause. The voting policy resulted in religious coercion of the minority by the majority.
• Zelman v. Simmons-Harris, 536 U.S. 239 (2002) A government program providing tuition vouchers for Cleveland schoolchildren to attend a private or religious school of their parents’ choosing was upheld, concluding that the vouchers were neutral towards religion and therefore did not violate the Establishment Clause.
• Kitzmiller v. Dover Area School District, 400 F. Supp. 2d 707 (M.D. Pa. 2005) Teaching intelligent design in public school biology classes violates the Establishment Clause of the First Amendment because intelligent design is not science and "cannot uncouple itself from its creationist, and thus religious, antecedents."
• Hosanna-Tabor Evangelical Lutheran Church and School v. Equal Employment Opportunity Commission, 565 U.S. ___ (2012) The Establishment and Free Exercise Clauses of the First Amendment bar suits brought on behalf of ministers against their churches, claiming termination in violation of employment discrimi­nation laws. The government is by the Establishment Clause barred from appointing ministers and can not interfere with the freedom of religious groups to select their own due to the Free Exercise Clause.

Freedom of association

• National Association for the Advancement of Colored People v. Alabama, 357 U.S. 449 (1958) The freedom to associate with organizations dedicated to the "advancement of beliefs and ideas" is an inseparable part of the Due Process Clause of the Fourteenth Amendment.
• Hurley v. Irish-American Gay, Lesbian, and Bisexual Group of Boston, 515 U.S. 557 (1995) Private citizens organizing a public demonstration have the right to exclude groups whose message they disagree with from participating.
• Boy Scouts of America v. Dale, 530 U.S. 640 (2000) Private organizations are allowed to choose their own membership and expel members based on their sexual orientation even if such discrimination would otherwise be prohibited by anti-discrimination legislation designed to protect minorities in public accommodations.

Freedom of petition

• United States v. Cruikshank, 92 U.S. 542 (1875) The Free Petition Clause enables persons to petition for everything connected with the powers or duties of the Federal Government. The right to petition is a primary right, while the right of assembly is a secondary right.
• Edwards v. South Carolina, 372 U.S. 229 (1963) The Free Petition Clause extends to the states through the Due Process Clause of the Fourteenth Amendment.
• California Motor Transport Co. v. Trucking Unlimited, 404 U.S. 508 (1972) The Free Petition Clause encompasses petitions to all three branches of the federal government—the Congress, the executive including administrative agencies and the judiciary.

Second Amendment rights

The right of the people to keep and bear arms

• District of Columbia v. Heller, 554 U.S. 570 (2008) Ruled that "The Second Amendment protects an individual right to possess a firearm unconnected with service in a militia, and to use that arm for traditionally lawful purposes, such as self-defense within the home."
• McDonald v. Chicago, 561 U.S. 3025 (2010) The Second Amendment right to keep and bear arms for self-defense is fully applicable to the states through the Fourteenth Amendment.

Legality of targeted firearms prohibition

• United States v. Miller, 307 U.S. 174 (1939) Held that a sawed-off shotgun did not constitute a weapon suitable for militia use, and therefore verified the constitutional integrity of the National Firearms Act. Prior to Heller, Miller was the primary ruling covering the individual right to bear arms, and its more conservative interpretation of individual rights (in the context of the militia) was the primary jurisprudential basis for subsequent legislation outlawing specific weapon types.

Other areas

• Fletcher v. Peck, 10 U.S. 87 (1810) For the first time the Court struck down a State law as unconstitutional. A State legislature (in this case, Georgia) can repeal a previous, corruptly made law (in this case, a land grant), but not void valid contracts made under this law.
• Dartmouth College v. Woodward, 17 U.S. 518 (1819) extended contract rights to corporations and established the differences between public and private corporations.
• Johnson v. M'Intosh, 21 U.S. 543 (1823) Private citizens cannot purchase lands from Native Americans.
• Barron v. Baltimore, 32 U.S. 243 (1833) The Bill of Rights cannot be applied to the state governments.
• Ex parte Milligan, 71 U.S. 2 (1866) Trying citizens in military courts is unconstitutional when civilian courts are still operating. Trial by military tribunal is constitutional only when there is no power left but the military, and the military may validly try criminals only as long as is absolutely necessary.
• Slaughter-House Cases, 83 U.S. 36 (1873) The Fourteenth Amendment protects only the "privileges or immunities" conferred by virtue of the federal United States citizenship to all individuals of all states within it, but not those privileges or immunities incident to citizenship of a state.
• The Paquete Habana, 175 U.S. 677 (1900) Ruled that federal courts could look to customary international law because it is an integrated part of American law.
• Lone Wolf v. Hitchcock, 187 U.S. 553 (1903) Congress has the power to break treaties with the Indian tribes without judicial review, the plenary power doctrine.
• Lochner v. New York, 198 U.S. 45 (1905) The "right to free contract" or "liberty of contract" is implicit in the Due Process Clause of the Fourteenth Amendment.
• Selective Draft Law Cases, 245 U.S. 366 (1918) The Selective Service Act of 1917 and, more generally, conscription do not violate the Thirteenth Amendment's prohibition of involuntary servitude or the First Amendment's protection of the freedom of thought.
• Dillon v. Gloss, 256 U.S. 368 (1921) Congress may set a deadline for the ratification of a new constitutional amendment if it wishes to do so.
• Gitlow v. New York, 268 U.S. 652 (1925) The First Amendment provisions protecting freedom of speech and freedom of the press apply not only to the Federal Government, but also to the governments of the individual states by the Fourteenth Amendment.
• Brown v. Mississippi, 297 U.S. 278 (1936) A defendant's confession that is extracted by police violence cannot be entered as evidence and violates the Due Process Clause.
• United States v. Curtiss-Wright Export Corp., 299 U.S. 304 (1936) While the Constitution does not explicitly say that all ability to conduct foreign policy is vested in the President, it is nonetheless given implicitly and by the fact that the executive, by its very nature, is empowered to conduct foreign affairs in a way that Congress cannot and should not. The President has "plenary" powers in the foreign affairs field that is not dependent upon congressional delegation.
• Erie Railroad Co. v. Tompkins, 304 U.S. 64 (1938) Federal courts do not have the power to create general federal common law when hearing state law claims under diversity jurisdiction (led to the development of the Erie doctrine).
• Coleman v. Miller, 307 U.S. 433 (1939) A proposed amendment to the Constitution is considered pending before the states indefinitely unless Congress establishes a deadline by which the states must act. Furthermore, Congress—not the courts—is responsible for deciding whether an amendment has been validly ratified.
• International Shoe v. Washington, 326 U.S. 310 (1945) Minimum contacts with the forum state can enable a court in that state to exert personal jurisdiction over a party consistent with the Due Process clause.
• Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579 (1952) The President of the United States can't seize private property in the absence of either specifically enumerated authority under Article Two of the United States Constitution or statutory authority conferred on him by Congress.
• Reid v. Covert, 354 U.S. 1 (1957) The Constitution supersedes all treaties ratified by the Senate.
• Williams v. Lee, 358 U.S. 217 (1959) State courts do not have jurisdiction on Indian reservations without Congressional authorization, to allow state infringement undermines tribal sovereignty.
• Baker v. Carr, 369 U.S. 186 (1962) The reapportionment of state legislative districts is not a political question, and is justiciable by the federal courts.
• Wesberry v. Sanders, 376 U.S. 1 (1964) The Constitution requires that members of the House of Representatives be selected by districts composed, as nearly as is practicable, of equal population.
• Reynolds v. Sims, 377 U.S. 533 (1964) A complimentary case on Baker v. Carr, which stated that districts must be of as equal population as mathematically possible, so as to ensure equal protection. This case also applied to districts in the federal House of Representatives.
• Menominee Tribe v. United States, 391 U.S. 404 (1968) Native American treaty rights are not abrogated without a clear and unequivocal statement by Congress and that statutes and treaties are to be construed liberally in favor of the tribe.
• Goldberg v. Kelly, 397 U.S. 254 (1970) Entitlement programs such as welfare conferred property rights on recipients, and their termination required procedural due process.
• San Antonio Independent School District v. Rodriguez, 411 U.S. 1 (1973) use of property tax as means to finance public education does not violate the Equal Protection Clause of the Fourteenth Amendment.
• Oneida Indian Nation of New York v. County of Oneida, 414 U.S. 661 (1974) there is federal subject-matter jurisdiction for possessory land claims brought by Indian tribes based upon aboriginal title, the Nonintercourse Act, and Indian treaties.
• Mathews v. Eldridge, 424 U.S. 319 (1976) Established test for deciding what process is due when procedural due process applies that balances (1) the government's interests, (2) the individual's interest, and (3) the likelihood of making an inaccurate decision using the existing procedures and probable value of additional procedural safeguards.
• Nixon v. General Services Administration, 433 U.S. 425 (1977) Congress has the power to pass an act directing the seizure and disposition, within the control of the Executive Branch, of the papers and tapes of a former president.
• Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837 (1984) A government agency's interpretation of its own mandate from Congress is entitled to judicial deference if the authority is ambiguous and the agency's interpretation is reasonable.
• Sony Corp. of America v. Universal City Studios, Inc., 464 U.S. 417 (1984) Making of individual copies of complete television shows for purposes of time-shifting does not constitute copyright infringement, but is fair use.
• Feist Publications v. Rural Telephone Service, 499 U.S. 340 (1991) Originality, not sweat of the brow, is the touchstone of copyright protection.
• Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993) Expert evidence must be generally accepted in the scientific community (Daubert standard).
• Nobleman v. American Savings Bank, 508 U.S. 324 (1993) Disallowed the use of cram downs for primary residences.
• Breard v. Greene, 523 U.S. 371 (1998) Rejected jurisdiction of International Court of Justice in a capital punishment case dealing with a citizen of Paraguay.
• Bush v. Gore, 531 U.S. 98 (2000) Ended the recount of ballots in Florida in the 2000 presidential election as violative of the Equal Protection Clause, effectively resolving the election in favor of George W. Bush.
• Hamdi v. Rumsfeld, 542 U.S. 507 (2004) The executive branch alone does not have the power to designate people as “enemy combatants” and then use that designation as a reason to hold them indefinitely without due process.
• Rasul v. Bush, 542 U.S. 466 (2004) The U.S. court system has the authority to decide whether foreign nationals (non-U.S. citizens) held in Guantanamo Bay were wrongfully imprisoned.
• Kelo v. City of New London, 545 U.S. 469 (2005) Local governments may seize property for economic development purposes.
• Hamdan v. Rumsfeld, 548 U.S. 557 (2006) Military commissions set up by the Bush administration to try detainees at Guantanamo Bay are illegal and lack the protections required under the Geneva Conventions and United States Uniform Code of Military Justice.
• Massachusetts v. Environmental Protection Agency, 549 U.S. 497 (2007) Greenhouse gases are air pollutants, and the Environmental Protection Agency may regulate their emission under the Clean Air Act.
• Boumediene v. Bush, 553 U.S. 723 (2008) Foreign terrorism suspects have constitutional rights to challenge their detention at the Guantánamo Bay naval base in United States courts.
• Association for Molecular Pathology v. Myriad Genetics, Inc., 569 U.S. ___ (2013) Naturally occurring DNA sequences, even when isolated from the body, cannot be patented, but artificially created DNA is patent eligible because it is not naturally occurring.
• Shelby County v. Holder, 570 U.S. ___ (2013) Section 4(b) of the Voting Rights Act of 1965, which contains the coverage formula that determines which state and local jurisdictions are subjected to federal preclearance from the United States Department of Justice before implementing any changes to their voting laws or practices based on their histories of racial discrimination in voting, is unconstitutional.