Washington CNN  — 

On one of the final days of the Supreme Court’s term, Chief Justice John Roberts pivoted.

On Thursday, he infuriated conservatives by voting – once again – in favor of the administration’s health care law. But on Friday, he issued a strong dissent from the Court’s ruling that cleared the way for same-sex marriage nationwide.

In doing so, Roberts did something he has never done before: He read parts of his dissent from the bench. It is a move the justices save only for cases they really care about, and in his 10 years on the bench, no other case prompted Roberts to take such a step.

It was a 24-hour period that revealed much about the man who leads the nation’s highest court and views judges as umpires who apply the rules but do not make them.

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In his dissent, Roberts argued that the issue of same-sex marriage should be decided not by the courts but by the public process.

“Just who do you think we are?” Roberts asked, calling the majority’s decision “an act of will, not legal judgment.”

He implored his audience to “understand well” what his dissent is about.

“It is not about whether, in my judgment, the institution of marriage should be changed to include same-sex couples,” he said. “It is instead about whether, in our democratic republic, that decision should rest with the people acting through their elected representatives, or with five lawyers who happen to hold commissions authorizing them to resolve legal disputes under the law.”

Note he refers to his brethren as “lawyers.”

Roberts said that the Constitution leaves no doubt about the answer.

“The people of a state are free to expand marriage to include same-sex couples, or to retain the historic definition,” he said.

Roberts eviscerated his colleagues for “stealing this issue from the people” and in doing so “casting a cloud” over same-sex marriage.

The opinion did not stray from fundamental principles of judicial restraint that Roberts expressed at his confirmation hearing when he spoke about his role as “calling balls and strikes.” Roberts said that the role of the Court as envisioned by the majority is “anything but humble and restrained.” He mentions the word “restraint” eight times in his 29 pages.

“The rhetoric of restraint in the chief justice’s dissent is certainly powerful, and in the ordinary case, he’s absolutely right that the courts should defer to democratic process,” said Stephen I. Vladeck, a Professor of Law at American University Washington College of Law and a CNN contributor. “But the whole point of having an independent and unelected judiciary is for days – and cases – like this one. And so, while his dissent today is deeply consistent with his broader ‘balls and strikes’ judicial philosophy, the real takeaway from today’s ruling is that every once in a while, the Court is, and is supposed to be, so much more than just an umpire.”

Roberts pointedly attacked the majority’s opinion that relied on the due process clause that Kennedy said gives gays and lesbians a fundamental right to marry.

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“If I were a legislator, I would certainly consider that view as a matter of social policy,” he said. “But as a judge, I find the majority’s position indefensible as a matter of constitutional law.”

And he worried about a limiting principle.

“It is striking how much of the majority’s reasoning would apply with equal force to the claim of a fundamental right to plural marriage,” Roberts said.

It is also striking that the four liberals on the bench joined Kennedy’s opinion in full, but chose not to write separately. Roberts, however, brings Justice Ruth Bader Ginsburg into his dissent, linking comments she has made repeatedly over the years about Roe v. Wade with the notion of Courts stepping into to take a decision out of the political process.

“As a thoughtful commentator observed about another issue … Heavy-handed judicial intervention was difficult to justify and appears to have provoked, not resolved, conflict,” Roberts wrote.

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He attributes the phrase to Ginsburg’s 1985 essay, “Some Thoughts on Autonomy and Equality in Reaction to Roe v. Wade.”

Ginsburg has often said that the Court should have limited its opinion in that case to the Texas statute at hand. But in an interview with the New York Times’ Adam Liptak in 2013, Ginsburg rejected an analogy comparing those comments to the issue of same-sex marriage. “I wouldn’t make that connection,” she told Liptak.

Roberts ends the opinion on a high note, urging those in favor of same-sex marriage to celebrate the decision.

He warns, however, “But do not celebrate the Constitution. It had nothing to do with it.”