Supreme Court Justice Sonia Sotomayor issued a public apology to Justice Brett Kavanaugh after criticizing him in personal terms during a speech at the University of Kansas School of Law.

"I made remarks that were inappropriate," Sotomayor said in a statement April 15. "I regret my hurtful comments. I have apologized to my colleague."

The dispute grew out of an immigration case involving police stops – an issue with particular resonance for Latino and working-class communities. Sotomayor suggested Kavanaugh was out of touch with those realities, saying he "probably doesn't really know any person who works by the hour or the piece like I do."

The episode drew notice for turning a legal disagreement into something more personal.

Sotomayor was right to apologize. What's more surprising is that she felt compelled to.

In today's political climate, personal attacks are routine. Members of Congress trade insults daily, and the president routinely sets the tone on social media. Against that backdrop, the Supreme Court operates by a different code, one where personal grievances are expected to stay separate from legal disagreement.

Why the Supreme Court justices behave differently

The Supreme Court is structured in a way that all but requires civility. In the 435-member House of Representatives, two feuding colleagues barely register. In the 100-member Senate, it matters more. But on a court of nine, a personal breakdown isn't just awkward; it can undermine the work itself.

The nature of the job reinforces that dynamic. Justices resolve questions of law, not political battles. The disagreements can be just as fierce, but they're less likely to curdle into judgments about one another's character.

There is also a deeper institutional instinct at play: a shared sense that the court's credibility depends on how its members conduct themselves.

Members of Congress have little incentive to protect their institution's credibility. Their primary incentive is reelection, and public conflict often serves that goal. The presidency can fall into the same pattern, though term limits place some boundary on it.

Supreme Court justices operate under different pressures. Life tenure insulates them from electoral politics, freeing them to focus less on how decisions affect their personal standing and more on how they reflect on the court as a whole.

The contrast is also about visibility. Congress is a public performance. Floor debates double as content for social media and fundraising appeals, with cameras encouraging members to play to an audience. The court, by design, works mostly in private – giving justices room for candid deliberation and, when needed, compromise.

The institution matters. So do the justices.

Institutional factors only go so far. Congress has had periods of genuine decorum, and the court has had moments of open hostility. Justices Hugo Black and Robert H. Jackson feuded so bitterly it spilled into public view. James Clark McReynolds refused to speak to or sit beside colleagues he disliked, in some cases because they were Jewish.

What sets the current court apart is not just its structure, but also the people on it. There is plenty of room to debate whether individual justices are consistent in their rulings. But it is hard to argue that any of them are acting in bad faith.

Even so, some justices believe civility is eroding. Justice Clarence Thomas recently reflected on a court that once "dealt with differences as friends," and wondered aloud whether that culture can survive in an era of social media, name-calling and mutual accusations of bad faith.

What is striking is that even in this diminished state, the Supreme Court remains the branch that behaves most like an institution.

The justices may no longer all be friends. But they still respect one another enough to recognize when a line has been crossed, and to say so publicly.

That culture is not guaranteed. It depends on who sits on the court. The institution encourages civility, but it cannot enforce it. In the end, it falls to the nine justices themselves to protect it.

Dace Potas is an opinion columnist for USA TODAY and a graduate of DePaul University with a degree in political science.

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