One year after a landmark constitutional decision on the nation’s new federal health care law, the U.S. Supreme Court in 2013 took historic steps in two civil rights cases that will define the Roberts court for some time to come.

Believing that national opinion on gay marriage was moving in their direction, civil rights groups optimistically awaited the justices’ rulings in two same-sex marriage cases on the October 2012 docket. However, they viewed a major challenge to the Voting Rights Act with considerable anxiety because of the Roberts court’s existing precedents on race and voting rights. Their feelings were justified on both counts.

In United States v. Windsor, a 5-4 majority led by Justice Anthony Ken­nedy struck down the definition of marriage as between a man and a woman in the federal Defense of Marriage Act. That definition, Kennedy said, injected inequality into every aspect of the U.S. Code. The definition, which affected rights and benefits in more than 1,000 federal laws, violated the equal protection guaranteed to legally married same-sex couples.

The Obama administration, in a remarkable turnaround, had refused to defend the federal law and then joined with the law’s opponents to urge its demise. Legally married same-sex couples almost immediately saw changes in a broad swath of areas, from health benefits to taxation.

The day before the same-sex marriage ruling, Roberts led a 5-4 majority in Shelby County, Ala. v. Holder to strike down the Voting Rights Act’s formula for determining which jurisdictions with a history of voting discrimination were required to have changes in voting practices approved by a federal court or the U.S. Department of Justice.

The formula, Roberts said, was unconstitutional because it was based on out-dated information and repudiated practices. The decision dealt the most serious defeat to civil rights groups in decades because they lost their most powerful legal tool against voting discrimination.

The following are other highlights of 2013 in the Supreme Court.

Following oral arguments in Fisher v. University of Texas, the outcome looked grim for the university’s continued use of race as a factor in its admissions policy. But the university and the challenger, Abigail Fisher, lived to fight another day when the justices, voting 7-1, sent the case back to the lower federal appellate court with directions to put teeth into its application of strict scrutiny.

The justices, however, were not done with racial preferences. In October, they heard Schuette v. Coalition to Defend Affirmative Action, Michigan’s defense of a state constitutional amendment banning race preferences in education. Stay tuned.

Justice Elena Kagan has described the high court’s Fourth Amendment docket as a “growth industry,” and cases in 2013 fed that hungry beast with a combination of high-tech and low-tech search-and-seizure controversies.

In Maryland v. King, a 5-4 court upheld Maryland’s law permitting police to take a DNA swab of the cheek of someone arrested, but not convicted, of a serious crime. And in two cases, involving drug-sniffing dogs named Franky and Aldo, the court ruled, 5-4, in Florida v. Jardines that a dog alert at the front door of a house where police suspected drugs were being grown constituted a search for the purposes of the Fourth Amendment, but it held unanimously in Florida v. Harris that a dog alert at a truck’s door can provide probable cause to search the vehicle.

In a pair of 5-4 job discrimination decisions issued on the same day in June, the court’s conservative majority continued a general trend of narrowly interpreting federal protections against job bias. In Vance v. Ball State University, the majority said a “supervisor” for purposes of Title VII liability is someone with power to take “tangible employment actions,” such as hiring and firing, not someone who just directs another employee’s day-to-day activities. And in University of Southwestern Texas Medical Center v. Nassar, the same majority imposed “but for” causation as the standard of proof in retaliation cases, a stricter standard of proof than for other Title VII claims.

The justices have been closely examining the requirements for certification of class actions and the role of class actions in arbitrations. In Comcast v. Behrend, a 5-4 majority held that plaintiffs must show at the class-certification stage whether damages could be decided on a classwide basis. And a 5-3 majority in American Express v. Italian Colors Restaurant said that waivers of class action arbitrations in arbitration agreements are strictly enforced under the Federal Arbitration Act.

The justices continued their fascination with patents in Association for Molecular Biology v. Myriad Genetics. A unanimous court, in a case involving gene mutations associated with breast cancer, said Myriad could not patent genes that it isolated in the bloodstream because natural occurring phenomena are not patentable, but a synthetic form of DNA was patent-eligible.

U.S. District Judge Beryl Howell on June 11 struck down the federal law banning demonstrations on the grounds of the court, finding the statute “unreasonable, substantially overbroad, and irreconcilable with the First Amendment.” Days later, Supreme Court Marshall Pamela Talkin promulgated a new regulation that invoked a different law to prohibit demonstrations on court grounds.•