One such study, conducted by Lee Epstein of Washington University in St. Louis and Mitu Gulati of the University of Virginia, concluded that over the century ending in 2021 the court ruled for businesses an average of 41 percent of the time. But the court led by Chief Justice John G. Roberts Jr. since 2005 decided for businesses 63 percent of the time.

The study showed a growing partisan divide between the justices. In 1953, the study’s authors wrote, “Democratic and Republican appointees are statistically indistinguishable, deciding on average about 45 percent of the cases in favor of the rich.” By 2022, they wrote, “that share is about 70 percent for the average Republican justice and 35 percent for the average Democratic justice.”