Sonia Sotomayor’s Most Notable Supreme Court Cases

Among the most notable Supreme Court cases involving Justice Sonia Sotomayor are her opinions on GPS tracking, cell phone location data, unlawful police stops, affirmative action, Texas’s abortion bounty law, the overturning of Roe v. Wade, lethal injection, unanimous jury verdicts, the Trump travel ban, and forced workplace arbitration. Since joining the Court in 2009 as the first Hispanic justice and the third woman to serve, she has written some of its most-read dissents and a handful of significant majority opinions, often returning to a single theme: how a legal rule actually works for the person it lands on.¹ Her prior work as a Manhattan prosecutor and federal trial judge shows through in that focus on consequences.²

Digital Privacy and the Fourth Amendment

Few areas of constitutional law have moved as quickly as the Fourth Amendment’s application to technology, and Sotomayor has been one of the Court’s most influential voices on where to draw the line.

United States v. Jones (2012)

Federal agents attached a GPS tracker to a suspect’s car and monitored his movements for 28 days. The warrant authorizing the device had expired, and the installation occurred outside the jurisdiction it specified. The Court unanimously held that the tracking was a search, but the justices split on the reasoning.³

Sotomayor’s concurrence went further than any other opinion in the case. She agreed that physically attaching the device was a trespass, but she argued that long-term electronic surveillance of someone’s movements reveals deeply private information — religious practices, political associations, medical visits, personal relationships — even when every individual trip happens on a public road. Taken together, the data creates a detailed map of a person’s life.

She also took direct aim at the third-party doctrine, which says people forfeit Fourth Amendment protection over information they share with others, like phone records or bank statements.⁴ Sotomayor called that framework “ill-suited to the digital age,” noting that people don’t meaningfully choose to share data when using a cell phone or browsing the internet, because those services can’t function without generating records.

Utah v. Strieff (2016)

An officer stopped a man leaving a house under surveillance without any specific reason to suspect him of a crime. During the stop, the officer ran his name, found an outstanding traffic warrant, arrested him, and searched him, turning up drugs. The majority held that the warrant broke the causal chain between the illegal stop and the evidence, so the drugs could be used at trial.⁵

Sotomayor’s solo dissent became one of the most widely read Supreme Court opinions in recent memory. She argued that the ruling gave officers a powerful incentive to stop people without justification, knowing they could simply check for warrants and use any hit to justify a search after the fact. Utah’s database contained over 180,000 outstanding warrants, so a hit was no surprise.

The final section, written only for herself, addressed what these stops mean for communities of color. She wrote that “people of color are disproportionate victims of this type of scrutiny” and described generations of Black and brown parents giving their children “the talk” about how to survive encounters with armed officers. The ruling, she wrote, “tells everyone, white and black, guilty and innocent, that an officer can verify your legal status at any time. It says that your body is subject to invasion while courts excuse the violation of your rights.”⁵

Carpenter v. United States (2018)

The seeds Sotomayor planted in Jones bore fruit six years later. The government obtained 127 days of historical cell-site location records, generated automatically when a phone connects to a nearby tower, without a warrant. In a 5–4 decision Sotomayor joined, the Court held that accessing this data is a search requiring a warrant.⁶

The majority declined to extend the third-party doctrine to cell-site records, reasoning that location data is fundamentally different from the bank records and phone logs at issue in older cases. Carrying a cell phone is practically unavoidable in modern life, and the phone logs location automatically without any action by the user. The Court adopted the logic Sotomayor had sketched in Jones: pervasive digital surveillance can reveal the “privacies of life” in ways the framers never imagined, and the law has to keep up.⁷

Affirmative Action and Equal Protection

Race-conscious admissions in higher education has been one of the most contested areas of constitutional law, and Sotomayor has been its most vocal defender on the Court. Her opinions share a consistent theme: formal colorblindness, applied to a society still shaped by racial inequality, locks in the advantages of those who already have them.

Schuette v. Coalition to Defend Affirmative Action (2014)

The Court upheld a Michigan constitutional amendment that banned race-conscious admissions at the state’s public universities. The 6–2 majority held that voters were free to change admissions policies through the democratic process.⁸

Sotomayor’s dissent argued that the amendment didn’t simply change a policy; it restructured the political process itself to disadvantage racial minorities. A white alumnus who wanted expanded legacy admissions could lobby the university’s board directly, but a Black applicant seeking a race-conscious admissions policy now had to amend the state constitution. Every other admissions preference could be addressed through normal channels. Only race required clearing a nearly impossible political hurdle, and that kind of structural disadvantage, she argued, triggers strict constitutional scrutiny.⁸

Students for Fair Admissions v. Harvard (2023)

The most consequential affirmative action ruling in decades effectively ended race-conscious admissions at universities nationwide. The 6–3 majority held that the admissions programs at Harvard and the University of North Carolina violated the Equal Protection Clause.⁹

Sotomayor’s dissent charged that the majority ignored both the history of the Fourteenth Amendment and the Court’s own precedent. She argued that the amendment was designed to undo the effects of a racial caste system, and that achieving racial equality sometimes requires race-conscious action rather than race-blind rules. She called the majority’s suggestion that universities could still consider race through applicants’ personal essays, so long as race was tied to individual qualities like “courage” or “determination,” an empty gesture that amounted to “lipstick on a pig.”¹⁰ The absence of racial diversity on campuses, she added, actually reinforces stereotyping, because students in homogeneous environments never encounter the range of perspectives within any racial group.

Abortion and Bodily Autonomy

Two cases decided within a year of each other reshaped reproductive rights law in the United States. Sotomayor dissented in both.

Whole Woman’s Health v. Jackson (2021)

Texas Senate Bill 8 banned most abortions after roughly six weeks of pregnancy, but it used an unusual mechanism. Instead of having state officials enforce the law, it authorized private citizens to sue anyone who performed or assisted a prohibited abortion, with a guaranteed minimum of $10,000 in statutory damages per violation. The design was deliberate: by keeping state officers out of enforcement, Texas aimed to prevent federal courts from blocking the law through the usual process of enjoining government officials.¹¹

The Court allowed the law to remain in effect during litigation, permitting only limited claims against certain licensing officials. Sotomayor dissented, arguing that the private-enforcement scheme was an end run around judicial review. “It cannot be the case that a State can evade federal judicial scrutiny by outsourcing the enforcement of unconstitutional laws to its citizenry,” she wrote. Her concern extended beyond abortion. If this structure worked, any state could insulate any unconstitutional law from challenge by deputizing private bounty hunters to enforce it.¹²

Dobbs v. Jackson Women’s Health Organization (2022)

The Court overturned Roe v. Wade and Planned Parenthood v. Casey, holding that the Constitution does not protect a right to abortion and returning the issue to state legislatures.¹³

Sotomayor joined the dissent written by Justices Breyer and Kagan, which argued that the right to bodily autonomy was “settled at the time of Roe, settled at the time of Casey, and settled yesterday.” The dissenters rejected the majority’s historical test, which asked whether a right was recognized when the Fourteenth Amendment was adopted, as inconsistent with how the Court analyzes other fundamental rights like marriage and intimate relationships. They also challenged the concurrence’s claim that returning abortion to the states was a “neutral” position, arguing that when the Court strips a right women held for fifty years, “the Court is not acting neutrally.”¹⁴

Religion, Speech, and Anti-Discrimination

The tension between religious liberty, free speech, and anti-discrimination protections has produced some of the Court’s sharpest divisions. Sotomayor’s dissents in this area warn that expanding one right at the expense of another creates real harm for vulnerable groups.

Kennedy v. Bremerton School District (2022)

The Court ruled in favor of a public high school football coach who knelt at midfield after games to pray, holding that his actions were protected private speech under the Free Exercise and Free Speech Clauses.¹⁵

Sotomayor’s dissent argued that the majority mischaracterized the facts by calling the prayers “quiet” and “private” when they had become a public spectacle at the 50-yard line. Public school students are uniquely susceptible to pressure from authority figures, and a coach’s visible prayer at a school event puts players in an impossible position: participate and signal agreement, or refuse and risk being seen as an outsider on the team. The Establishment Clause, she argued, exists precisely to prevent the government from placing students in that dilemma. By reframing a coach’s on-duty conduct as purely personal expression, the Court allowed a public official to bring religious exercise into a government-sponsored event.

303 Creative LLC v. Elenis (2023)

The Court held that the First Amendment prohibits Colorado from requiring a website designer to create wedding websites for same-sex couples if doing so conflicts with her religious beliefs. The majority treated the websites as “pure speech” that the state could not compel.¹⁶

Sotomayor’s dissent called the ruling the first time in history the Court granted a business open to the public a constitutional right to refuse service to a protected class. Public accommodations laws embody a basic social contract: a business that chooses to sell to the public takes on a duty to serve the public without unjust discrimination. By allowing businesses to define the “expressive quality” of their services in ways that exclude certain customers, she warned, the decision could reach far beyond wedding websites. A stationer could refuse to sell birth announcements to disabled couples, or a portrait studio could serve only “traditional” families.¹⁶

Trump v. Hawaii (2018)

The Court upheld a presidential proclamation restricting entry from several predominantly Muslim countries, finding that it fell within the executive’s broad authority over immigration and survived rational-basis review.

Sotomayor’s dissent argued that the majority applied a “watered-down” standard of review and ignored overwhelming evidence that the policy was motivated by anti-Muslim hostility. She pointed to the President’s own campaign statements calling for a “total and complete shutdown of Muslims entering the United States” and to advisers who were instructed to find a legal way to achieve that goal. The inclusion of North Korea and Venezuela, she wrote, was “insubstantial, if not entirely symbolic” window dressing. She drew a direct comparison to Korematsu v. United States, the wartime Japanese internment case, arguing that the majority “redeploys the same dangerous logic” by “blindly accepting the Government’s misguided invitation to sanction a discriminatory policy … all in the name of a superficial claim of national security.”¹⁷

Criminal Procedure and the Rights of the Accused

Sotomayor’s years as a prosecutor and trial judge show up most clearly in criminal cases, where her opinions focus on the concrete mechanisms that protect, or fail to protect, defendants from unfair outcomes.

Glossip v. Gross (2015)

The Court upheld the use of midazolam as the first drug in Oklahoma’s three-drug lethal injection protocol, rejecting the argument that it failed to render inmates sufficiently unconscious before the other two drugs, which cause paralysis and cardiac arrest, took effect.¹⁸

Sotomayor dissented, arguing that the majority relied on scientifically unsupported testimony about midazolam and imposed an entirely new requirement: that inmates identify an available alternative method of execution before they can challenge the existing one. She found that requirement absurd on its face. “It would be odd if the constitutionality of being burned alive, for example, turned on a challenger’s ability to point to an available guillotine.” The scientific evidence, she argued, showed that midazolam has a ceiling effect that prevents it from producing the deep unconsciousness needed to block the pain caused by the second and third drugs, leaving inmates potentially “exposed to what may well be the chemical equivalent of being burned at the stake.”¹⁸

Maples v. Thomas (2012)

This is one of Sotomayor’s most significant majority opinions. Cory Maples, a death row inmate in Alabama, missed a critical filing deadline because the two attorneys handling his post-conviction appeal had left their law firm without telling him or the court. The deadline notices were returned to the court unopened. By the time a local attorney noticed what had happened, the window for appeal had closed.¹⁹

Writing for a 7–2 majority, Sotomayor held that Maples had demonstrated the “cause” needed to excuse his procedural default. When attorneys abandon a client without notice, the normal rule that a lawyer’s mistakes bind the client breaks down. The attorney-client relationship has been severed, and the client cannot be faulted for failing to act on his own behalf when he has no reason to believe his lawyers have stopped representing him.²⁰

Ramos v. Louisiana (2020)

The Court held that the Sixth Amendment right to a unanimous jury verdict applies in state criminal trials, overruling a fractured 1972 decision that had allowed Louisiana and Oregon to convict defendants on 10–2 or 11–1 votes.²¹

Sotomayor joined the majority and wrote a separate concurrence focused on a point the other opinions touched on but did not fully confront: the racist origins of the non-unanimous jury rules. Louisiana adopted its rule at a constitutional convention in 1898 that was explicitly designed to “establish the supremacy of the white race,” and Oregon’s followed the rise of the Ku Klux Klan in the 1930s. These states never meaningfully reckoned with that history when they later reenacted the rules, and policies traceable to intentional racial discrimination that continue to produce discriminatory effects offend the Equal Protection Clause.²¹

Workers’ Rights and Forced Arbitration

In Epic Systems Corp. v. Lewis (2018), the Court held that employers can require workers to sign arbitration agreements that waive the right to bring collective or class action lawsuits, and that the Federal Arbitration Act takes priority over the protections of the National Labor Relations Act.²²

Sotomayor joined Justice Ginsburg’s dissent, which argued that the decision gutted one of the core protections Congress created to address the imbalance of power between employers and employees. When workers are forced to pursue claims one at a time in private arbitration, often with confidentiality provisions and no precedential value, employers can effectively insulate themselves from accountability. Claims too small to justify individual litigation go unenforced, and the dissent predicted this “enforcement gap” would widen as employers recognized the cost-benefit advantages of underpaying workers who have no realistic path to challenge the practice.²²

Across these cases, a pattern holds: Sotomayor asks whether abstract legal rules actually function as written when applied to people who lack the resources, information, or leverage to assert their rights individually. Her position is that formal legal equality means little when structural imbalances make it impossible for one side to use.

1
United States Senate Committee on the Judiciary. Associate Justice of the U.S. Supreme Court – Sonia Sotomayor
2
Oyez. Sonia Sotomayor
3
Justia U.S. Supreme Court Center. United States v. Jones, 565 U.S. 400 (2012)
4
Justia U.S. Supreme Court Center. United States v. Miller, 425 U.S. 435 (1976)
5
Justia U.S. Supreme Court Center. Utah v. Strieff, 579 U.S. ___ (2016)
6
Justia U.S. Supreme Court Center. Carpenter v. United States, 585 U.S. ___ (2018)
7
Supreme Court of the United States. Carpenter v. United States
8
Justia U.S. Supreme Court Center. Schuette v. Coalition to Defend Affirmative Action, 572 U.S. 291 (2014)
9
Justia U.S. Supreme Court Center. Students for Fair Admissions Inc. v. President and Fellows of Harvard College, 600 U.S. 181 (2023)
10
Supreme Court of the United States. Students for Fair Admissions Inc. v. President and Fellows of Harvard College
11
Supreme Court of the United States. Whole Woman’s Health v. Jackson
12
Justia U.S. Supreme Court Center. Whole Woman’s Health v. Jackson, 595 U.S. ___ (2021)
13
Justia U.S. Supreme Court Center. Dobbs v. Jackson Women’s Health Organization, 597 U.S. ___ (2022)
14
Supreme Court of the United States. Dobbs v. Jackson Women’s Health Organization
15
Supreme Court of the United States. Kennedy v. Bremerton School District
16
Supreme Court of the United States. 303 Creative LLC v. Elenis
17
Supreme Court of the United States. Trump v. Hawaii
18
Justia U.S. Supreme Court Center. Glossip v. Gross, 576 U.S. 863 (2015)
19
Justia U.S. Supreme Court Center. Maples v. Thomas, 565 U.S. 266 (2012)
20
Supreme Court of the United States. Maples v. Thomas, Commissioner, Alabama Department of Corrections
21
Supreme Court of the United States. Ramos v. Louisiana
22
Justia U.S. Supreme Court Center. Epic Systems Corp. v. Lewis, 584 U.S. ___ (2018)