Is the Supreme Court heading for a conservative revolution?

But precedents aren’t overturned only because of the justices’ ideological leanings — other factors play a role, too. Sometimes there are philosophical differences, as in the case of Justice Clarence Thomas, who is notoriously skeptical of loyalty to precedent for precedent’s sake alone. In a concurring opinion a few months ago, he wrote, “When faced with a demonstrably erroneous precedent, my rule is simple: We should not follow it.” Thomas is not necessarily alone in this regard, although he is unusually open about his views. Other justices have also varied on how much they seem to lean on precedent. According to one study using data from the Burger and Rehnquist courts, Justice Ruth Bader Ginsburg was more likely to show deference to precedent than Kennedy. The stature of the precedent in question can matter, too. For instance, one study found that justices were more likely to overrule a precedent that they disagreed with if it was also still active and influential, as was the case when the conservative justices overturned a longstanding ruling involving public sector unions in 2018.

There may also be moments when a wing of the court feels more emboldened to overturn precedents — like when the court’s ideological center of gravity shifts. In 2006, for instance, Justice Sandra Day O’Connor, then the court’s “swing” justice, was replaced by Samuel Alito, a reliable conservative. The following term, the court issued five precedent-altering decisions — more than in any other single year since — including a case where the conservatives voted to allow a ban on a specific method of abortion for the first time. Ryan Black, a political science professor at Michigan State University, said it’s possible that this year could be similar. “It’s the same pattern — the median moved right, and the conservative wing of the court is stronger and more homogenous, so it’s not unreasonable to expect they might want to strike while the iron is hot,” he said.