(CNN) — Name a major political issue from the past few decades, and chances are that Justice Anthony Kennedy authored the landmark decision on it during his time on the Supreme Court.
Since his ascension to the court in 1988, Kennedy has authored some of the judicial body’s biggest rulings of the past few decades, for both conservative and liberal positions. Here’s a look at five of those decisions that deeply impacted the course of America’s political, cultural and social life.
Planned Parenthood v. Casey (1992)
Upheld right to abortion, with restrictions
In a rare triple-byline, Kennedy co-authored with Justices Sandra Day O’Connor and David Souter an opinion reaffirming the right to abortion as guaranteed by Roe v. Wade. The opinion angered conservatives while allowing restrictions that reproductive rights groups are still fighting today.
The opinion stemmed from a lawsuit over changes to Pennsylvania’s abortion control law in 1988 and 1989.
The new version of the law included requirements of a 24-hour wait period, parental consent for minors, spousal notification and the disclosure of information by a physician (informed consent) before a woman could seek an abortion.
These provisions were challenged by several abortion clinics and physicians, including Planned Parenthood of Southeastern Pennsylvania, who sued Gov. Robert Casey.
The court reaffirmed the right to abortion, but it upheld all the provisions except for spousal notification.
The 5-4 decision also introduced the “undue burden” standard to determine if a state law imposes a “substantial obstacle in the path of a woman seeking an abortion before the fetus attains viability.”
Roper v. Simmons (2005)
Banned the death penalty for juveniles
The death penalty case concerned Christopher Simmons, who committed capital murder when he was 17 years old and was sentenced to death. The question before the court was whether the death penalty, the government’s harshest punishment, could be applied to those under 18.
Justice Kennedy wrote the ruling in the 5-4 decision, saying that executing juveniles is cruel and unusual punishment banned by the Eighth Amendment. He argued that juveniles have developing minds and so are not beyond reform.
“When a juvenile offender commits a heinous crime, the State can exact forfeiture of some of the most basic liberties,” he wrote, “but the State cannot extinguish his life and his potential to attain a mature understanding of his own humanity.”
The decision was part of a series of decisions limiting the death penalty over the past two decades and came three years after Atkins v. Virginia, which ruled that executing the mentally disabled was unconstitutional.
Boumediene v. Bush (2008)
Rights for Guantanamo Bay detainees
In a major ruling of the post-9/11 era, Kennedy wrote it is unconstitutional to prevent detainees from going before a judge and challenging their detention — known as the writ of habeas corpus — even if they are designated as enemy combatants or held in a different country.
Boumediene argued that he and other petitioners were unconstitutionally denied the writ of habeas corpus. The government argued that the Military Commissions Act, passed by Congress in 2006, denied enemy combatants that right.
Kennedy wrote for the majority opinion in the 5-4 decision. “Our basic charter cannot be contracted away like this. The Constitution grants Congress and the President the power to acquire, dispose of, and govern territory, not the power to decide when and where its terms apply,” Kennedy wrote.
“Abstaining from questions involving formal sovereignty and territorial governance is one thing. To hold the political branches have the power to switch the Constitution on or off at will is quite another.”
Citizens United v. FEC (2010)
Ended limits on political spending
The case began with Citizens United, a nonprofit corporation that wanted to advertise for a movie critical of Hillary Clinton ahead of the 2008 presidential election. However, federal law set strict limits on the ability of corporations and unions to spend and attempt to influence elections.
The case pit campaign finance restrictions against Citizens United’s claim that businesses have First Amendment free speech rights.
Writing for the 5-4 majority, Kennedy sided with the company and struck down limits on independent campaign spending by corporations and unions.
“When government seeks to use its full power, including the criminal law, to command where a person may get his or her information or what distrusted source he or she may not hear, it uses censorship to control thought,” Kennedy wrote for the majority. “The First Amendment confirms the freedom to think for ourselves.”
Obergefell v. Hodges (2015)
Legalized gay marriage
Kennedy authored the historic opinion that established a new civil right for same-sex couples to marry nationwide.
Groups of same-sex couples in Ohio, Michigan, Kentucky, and Tennessee sued their relevant state agencies to challenge the constitutionality of bans on same-sex marriage or the refusal to recognize legal same-sex marriages.
The plaintiffs claimed that the statutes violated the Equal Protection Clause and Due Process Clause of the Fourteenth Amendment. One couple also brought claims under the Civil Rights Act. In all the cases, the trial court found in favor of the plaintiffs, but the 6th Circuit Court of Appeals reversed those decisions.
The appeal of Jim Obergefell of Ohio, whose husband died of ALS before the case was heard, and three others were consolidated for the high court.
In an opinion equal parts jurisprudence and poetry, the court held that the right to marry is one of the fundamental liberties protected by Due Process Clause of the Fourteenth Amendment, one that applies to same-sex couples just as it does to everyone else.
“No union is more profound than marriage, for it embodies the highest ideals of love, fidelity, devotion, sacrifice and family,” Kennedy wrote in the 5-4 ruling. “In forming a marital union, two people become something greater than they once were.”