In a dissent to the majority’s opinion in Glossip v. Gross, which upheld Oklahoma’s use of a key drug used for lethal injections, Justice Stephen Breyer, joined by Justice Ruth Bader Ginsburg, called for a renewed legal debate over the death penalty.

The court has not ruled on the constitutionality of the death penalty at-large since Gregg v. Georgia in 1976 — though it has examined various aspect of death penalty protocols, including applying the punishment to the mentally handicapped, to minors, and via various methods — and Breyer wrote that “[t]he circumstances and the evidence of the death penalty’s application have changed radically since then.”

“Given these changes, I believe that it is now time to reopen the question,” he wrote, adding that the past 40 years of the death penalty in America have led him to believe “that the death penalty, in and of itself, now likely constitutes a legally prohibited ‘cruel and unusual punishmen[t].’”

The fact that the death penalty is applied so sporadically “is the antithesis of the rule of law,” Breyer wrote. Citing numerous studies, the justice concluded that “the factors that most clearly ought to affect application of the death penalty — namely, comparative egregiousness of the crime — often do not. Other studies show that circumstances that ought not to affect application of the death penalty, such as race, gender, or geography, often do.”

Breyer also cited concerns about “excessive delays” in death penalty proceedings and observed that around 20 states have abolished the death penalty outright, while many more have not executed an inmate in years. And he pointed to an emerging global consensus on the death penalty, noting that a clear majority of United Nations member countries have ceased executions over the past few decades.

Breyer and a number of other justices have previously expressed their personal opposition to the death penalty, but few have expressed outright the belief that the punishment violates the Eighth Amendment’s ban on cruel and unusual punishment. At one point in 2011, Breyer told an audience at the World Affairs Council of Philadelphia that “[o]nly the legislature can abolish the death penalty,” before arguing that public opinion could be swayed on the issue via politics.

But Breyer, in his dissent in Glossip v. Gross, recognized that while the issue of the death penalty, in and of itself, perhaps could be viewed as a legislative matter, “the matters I have discussed, such as lack of reliability, the arbitrary application of a serious and irreversible punishment, individual suffering caused by long delays, and lack of penological purpose are quintessentially judicial matters.”

He concluded, “At the very least, the Court should call for full briefing on the basic question” of the death penalty.

The larger case at hand, Glossip v. Gross, did not deal explicitly with the constitutionality of the death penalty per se, but rather whether or not the state of Oklahoma’s use of the drug midazolam as an anesthetic before executions prevented cruel and unusual punishment. Justice Samuel Alito, writing for the majority, argued that it did not, while Justice Sonia Sotomayor, joined by the court’s three other Democratic appointees, dissented. (The decision “leaves petitioners exposed to what may well be the chemical equivalent of being burned at the stake,” Sotomayor wrote.)

Justices Antonin Scalia and Clarence Thomas, in separate concurring opinions, were the only two to respond directly to Breyer’s arguments regarding the overall constitutionality of the death penalty.

In typically colorful prose, Scalia said that it was “Groundhog Day” and that Breyer was trying to revive a long line of anti-death penalty activism even though the Constitution states that “no person … shall be deprived of life … without due process of law,” effectively referring to death penalty practices in place at the time of the founders.

Scalia referred to Breyer’s argument as “gobbledy-gook,” while Thomas called it “pseudoscientific” and based upon an “imaginary constitutional rule against ‘arbitrariness’.”

Later, Scalia wrote that Breyer’s logic saying excessive delays, caused by anti-death penalty activists, make the practice unconstitutional “calls to mind the man sentenced to death for killing his parents, who pleads for mercy on the ground that he is an orphan.”

He concluded, “Justice Breyer does not just reject the death penalty, he rejects the Enlightenment” for arguing against a punishment that even the acclaimed moral philosopher Immanuel Kant supported.

Though the case ultimately left the feud between the two Republican appointees and two Democratic appointees unresolved, Richard Dieter of the Death Penalty Information Center, which largely opposes the death penalty, said the vigorous debate sets up a future challenge.

“The death penalty itself, I think, is in trouble,” Dieter said, pointing to previous decisions from Justice Anthony Kennedy suggesting he might someday side with Breyer on the issue. Justices Elena Kagan and Sonia Sotomayor, Dieter added, are likely sympathetic to Breyer’s reasoning despite their decisions not to sign the tangential dissent.

“[Breyer’s dissent] says the court should be ready to debate the very constitutionality of the death penalty,” considering it as it’s applied in the 21st century and not as it was debated in the 1970s, Dieter concluded. “Times have changed.”