The Supreme Court is supposed to be insulated from most political pressures. In fact, one of its primary roles is to serve as a counterweight to the will of the majority in cases where policies might impinge on the rights of other citizens.
Yet it is common to hear criticism that the court is out of step with the American public. How well does the court actually represent the views of the American public? And how might this change with the Supreme Court nomination of Judge Brett Kavanaugh, a more solidly conservative jurist than Anthony Kennedy?
Historically, it’s been difficult to determine the precise ideological position of the court. Standard measures of the political preferences of citizens are quite different in nature from the positions taken by justices on Supreme Court cases.
But we came up with a way to compare the ideological position of the Supreme Court and its individual justices with the views of Americans. In our study, we asked ordinary Americans to describe their views on issues that had recently been decided by the court.
What we discovered was shocking: Virtually all of the justices on the court occupied extreme ideological positions when compared with the American public. The justices in the court’s conservative wing, including Chief Justice John Roberts, are not just more conservative than a typical member of the American electorate — they are also all to the right of the typical Republican.
Similarly, the four liberal members of the court fall well to the left of the median American voter and are in fact more liberal than a majority of those who identify as Democrats.
In recent decades, the Supreme Court has had as its median voter a moderate — most recently, Justice Kennedy, preceded by Sandra Day O’Connor. This pivotal member of the court has fallen quite close to the public center.
The overall ideological position of the Supreme Court fell approximately at the position of Justice Kennedy. Despite the relatively extreme positions taken by most of its members, the court has been, on balance, representative of the views of Americans.
But with the nomination of Judge Kavanaugh, that could change. He seems likely to be at least as conservative as, and perhaps more so than, Chief Justice Roberts, which would make the latter the court’s new ideological median. And our study found that he is much more conservative than both the average American voter and the average Republican voter.
In fact, Chief Justice Roberts was estimated to be more conservative than nearly 90 percent of Americans — and even three-quarters of Republicans.
To give an example of how this might play out: Justices Kennedy and Chief Justice Roberts were on opposite sides of the Obergefell v. Hodges decision that legalized gay marriage. According to recent polling by Gallup, 67 percent of Americans agreed with Justice Kennedy’s position on the case. With Judge Kavanaugh on the court and Chief Justice Roberts as the swing justice, the court would shift to being out of step on this issue with the views of two-thirds of Americans.
Now, Chief Justice Roberts has shown that he is deeply concerned about preserving the legitimacy of the Supreme Court as an institution. Perhaps he will become more moderate over time.
But our study suggests that the Supreme Court’s ideological representativeness has been a result more of chance than of any fundamental tendency of the court or its members. Looking ahead, we would predict that the court will be even more polarized — and is unlikely to come even close to reflecting the views of most Americans.
Stephen A. Jessee is an associate professor of political science at the University of Texas at Austin. Neil Malhotra is a professor of political economy in the Graduate School of Business at Stanford.
Follow The New York Times Opinion section on Facebook and Twitter (@NYTopinion), and sign up for the Opinion Today newsletter.