Justice Antonin Scalia’s chair at the Supreme Court was draped in black to mark his death in February. Without Scalia, conservatives’ hopes for transformational decisions were dashed. (J. Scott Applewhite/AP)

Conservative hopes for a transformational term at the Supreme Court ended with Justice Antonin Scalia’s death this winter, and liberals instead prevailed on what are likely to be the term’s most influential decisions.

The cases and causes that had the right so excited at the beginning of the term — challenges to affirmative action, restrictions on abortion, complaints about labor union fees, bold attacks on the way electoral districts are drawn and President Obama’s use of executive power — ended either with liberal victories or draws that set no precedent.

“The era of aggressive conservative legislation and litigation in the Supreme Court may largely be over, unless and until Justice Scalia is replaced by someone like-minded,” said Pamela S. Karlan, a Stanford University law professor and a leader in the liberal American Constitution Society. “Each of these cases was an attempt to push the law sharply to the right, and the court doesn’t seem to have the appetite for this.”

As has been the case for more than a decade, Justice Anthony M. Kennedy again was the court’s pivotal player, and he gave the left important and somewhat surprisingly broad victories.

The Post's Robert Barnes explains the big decisions in this Supreme Court session and how the absence of a justice will continue to affect it. (Gillian Brockell/The Washington Post)

But it was the absence of Scalia, the bombastic senior justice whose intellect and bravado powered the court’s conservative wing, that altered the court’s tone and reversed its reputation as a welcoming place for conservative causes.

“It has long been said that if you add one new justice, you get an entirely new court,” said Washington lawyer Gregory G. Garre, a former solicitor general for President George W. Bush. “This term showed that if you take away a justice, you get an entirely new court.”

Elizabeth Slattery, a legal fellow at the conservative Heritage Foundation, said that the “theme of the term is the void that Justice Scalia left behind. We lost one of the greatest voices.”

Without the perpetually in-the-spotlight Scalia, other members of the court emerged. Justice Clarence Thomas asked questions at oral argument for the first time in a decade — albeit just once — and assumed the role of the chief defender of gun rights.

Thomas’s ideological opposite, Justice Sonia Sotomayor, used a series of sharply worded dissents to speak frankly about race, discrimination and what she sees as inequality in the justice system. “She is becoming the heir to Thurgood Marshall,” said Neal Katyal, a former acting solicitor general in the Obama administration.

Justice Stephen G. Breyer wrote the no-frills, just-facts opinion striking down Texas’s widely replicated restrictions on abortion clinics. Some see him as having a role in moving Kennedy on affirmative action and helping the eight-member court reach narrow decisions that allowed consensus rather than gridlock.

Justice Samuel A. Alito Jr. took on Scalia’s role as dissenter, airing from the bench his disagreements with the majority on abortion and affirmative action. But unlike Scalia, he lacks a love of the whip. Most of his dissent in the abortion case was a detailed explanation of how procedural rules should have barred the court from hearing the complaints of the Texas clinic owners.

Justice Ruth Bader Ginsburg wrote for the court a decision that turned back a conservative attempt to change the way state and local governments use the “one person, one vote” principle in a way that would have aided rural, conservative areas.

And she issued a succinct concurrence warning against future incursions on the right to an abortion. “So long as this court adheres to Roe v. Wade,” Ginsburg wrote, abortion laws that “do little or nothing for health, but rather strew impediments to abortion . . . cannot survive judicial inspection.”

In general, the temperature at the court this term was more moderate. There was no landmark case, such as last year’s same-sex-marriage case. Moreover, with the realization that the Republican-controlled Senate was not going to vote on Obama’s nominee, Judge Merrick Garland, and restore the court to full strength, the justices seemed to adopt a we’re-all-in-this-together attitude.

“Gone were the souring and scorching rhetoric of the Scalia dissent,” Garre said.

Chief Justice John G. Roberts Jr. played down the trouble the court had in reaching decisions with only eight members. “Sometimes we talk about cases longer to see if we can reach some type of agreement. But that’s it,” he told a group of judges and lawyers in Arkansas. “There are reasons most appellate courts have an odd number of judges. But the process is pretty much what it has been.”

But Justice Elena Kagan publicly praised Roberts for pushing the court to find compromise. (She did her part, siding with Roberts and Kennedy about as often as she did with her fellow liberals.)

However, the court still deadlocked on the labor union case, Obama’s plan to shield millions of undocumented immigrants from deportation and a handful of other cases. Seemingly tied on whether religiously affiliated groups could be freed from the Affordable Care Act’s requirement that they provide workers with contraceptive coverage, the justices sent the cases back to lower courts in the hope they could reach a compromise.

“I think what you’re seeing is a seriously crippled court,” said Steven R. Shapiro, legal director of the ACLU.

Conservatives said the relatively small number of cases in which the court could not reach a decision shows that there is not a pressing need to fill Scalia’s seat, as Democrats claim. But Elizabeth Wydra, president of the liberal Constitutional Accountability Center, disagreed.

The labor union case was one in which the tied vote kept the status quo in place, with an outcome Wydra favored. But she said she still thought it was wrong that major policy has been decided “with a single-sentence affirmance” of a lower-court decision rather than a reasoned opinion of the Supreme Court.

The failure to reach an agreement on Obama’s immigration plan, which aimed to shield millions of undocumented immigrants from deportation and give them the right to work legally in the United States, meant that a national policy was blocked by a district judge and a 2-to-1 vote of an appeals court panel, Wydra noted.

The Supreme Court was able to reach wide agreement on a clutch of election law cases by narrowing the results. Besides the one-person, one-vote case from Texas, the justices upheld a judge-drawn Virginia congressional redistricting plan that created a new district conducive to a minority candidate, and they approved of a plan drawn by Arizona’s independent panel. All three decisions were favorable to Democrats.

There was no movement on the call from Breyer and Ginsburg at the end of last term that the constitutionality of the death penalty be reexamined. But the court threw out Florida’s death penalty process, raised doubts about cases in other Southern states and, in a strongly worded opinion from Roberts, vacated the death sentence given to a young black man in Georgia by an all-white jury.

Shapiro and Katyal mentioned that the justices seem increasingly drawn into the debate outside the court about racial bias in the criminal justice system. The issue “is seeping into Supreme Court debate and Supreme Court decision-making in ways that are powerful,” Shapiro said.

In the end, the biggest decisions came back to Kennedy. Before writing his opinion in the University of Texas affirmative-action case, Kennedy had never approved of a race-conscious program, although he had not been as willing as his colleagues to outlaw the use of race.

Prior to the abortion decision, he had found only one statute unlawful — requiring a woman to inform her husband of her decision to have the procedure — among dozens the court had reviewed.

The next president will shape the future of the aging court, but Garre wondered if its move to the left has already begun.

“Justice Kennedy had the biggest impact on the most important cases, and you have to wonder whether we have already seen a meaningful shift in the court, regardless of who fills Justice Scalia’s seat,” he said.