This scrupulously objective book may be considered a gift to conservatives who have long despaired about the possibility of principled legal tenets regularly prevailing in Supreme Court opinions. For decades this long-suffering group has watched Republican Supreme Court appointees concur in various left-wing crackpot decisions that have become the law of the land.

Thankfully, such disappointments should become less likely, according to authors Neal Devins, a College of William & Mary law professor, and Lawrence Baum, professor emeritus of political science at Ohio State University. Nowadays, conservatives have their own elite legal organizations that mold and encourage those with judicial potential and from which the judicial aspirants draw support and esteem. In addition, products of the conservative elite now make up the majority of the Supreme Court.

But uncertainty remains. Will this new conservative court maintain its objectivity and independence in considering complex legal matters, or will it adopt the reasoning of the position-paper-type opinions about legal topics that circulate within respectable, corporate conservatism?

In advancing their social-psychology theory about the current state of the Supreme Court, Devins and Baum first make some unremarkable observations about human nature in general and judicial personalities in particular. They note that the psychology of a Supreme Court justice disproportionately values power and admiration over other goals such as riches or privacy. Furthermore, the justices have traditionally acquired self-esteem by pleasing the legal, academic, and journalistic elites with whom they have associated, and not the general public—about whose opinion they care little, if at all.

But whereas in the past, the elites came in one political flavor at a time—conservative in the early 1900s and liberal from about 1950 to 1985—competing liberal and conservative elites exist today. Liberal elite praise, say the authors, likely contributed to Republican Supreme Court appointees like Harry Blackmun drifting to the left during their tenures. Applying their social-psychology model to the current world of divided elite opinion, the authors conclude that the days of such drift are over.

The Supreme Court justices have traditionally come to their legal determinations through class consciousness. No more. While justices have always reflected the philosophies of their elite environments, Republican and Democratic appointees formerly shared the same environments. Hence, the justices’ majority and dissenting opinions did not sort by party; rather “class status transcended party and ideology,” Devins and Baum write. In fact, they note that from 1790 to 1937, of the 322 most important Supreme Court cases and the ones in which at least two justices dissented, “only one case divided all the Court’s Republican-appointed Justices from all of their Democratic-appointed colleagues—and the division in that decision is ambiguous.”

Early on, the Court often sided with business interests against government regulation. But during FDR’s presidency, the court modified its philosophy to acquiesce in such government regulation, as seen in the court’s remarkable overturning from 1937 to 1946 of 32 lower-court decisions that curtailed government regulation. After firmly establishing the constitutionality of economic regulation, the court moved on to civil liberties.

The legal environment established during the New Deal era was completely different from that of today. Beginning in the 1950s, the legal establishment, notably the American Bar Association, moved left and the legal academy moved even further left. Other liberal legal advocacy groups like the NAACP and the ACLU were actively litigating during that time. No conservative counterweight existed. Although, in general, Republicans were more conservative than Democrats, southern Democrats were far more conservative than New England Republicans. Unlike today, regional identities trumped party identities.

Presidents between the 1950s and the 1970s considered judicial philosophy when making Supreme Court appointments, but other factors prevailed. President Richard Nixon wanted justices who would be sympathetic to his war on crime but who would not alienate liberal Eastern Republicans. “Judicial restraint,” or deference to the elected branches of government on policy matters, became a common Republican slogan. On the other hand, when making their appointments, Democratic presidents considered their southern constituents while also showing they valued diversity. Which party controlled the Senate also affected the selection.

Ideology was generally a secondary consideration during presidential appointments at that time, as the book’s various graphs reveal that Republican-appointed Justice John Paul Stevens was the most liberal justice on the court from 1991 until his 2010 retirement. From 1991 to 1993, the three most liberal justices were Republican appointees: Stevens, Harry Blackmun, and David Souter.

But things began to change under the influence of President Ronald Reagan’s second attorney general, Edwin Meese. In 1982, students at both Yale and the University of Chicago law schools created the Federalist Society to counter the liberal bias in law schools and the legal profession. When Meese took office in 1985, his Department of Justice looked to the Federalist Society as it “took steps to groom a cadre of well-credentialed conservative lawyers, and in doing so, transform constitutional discourse and judicial decision making over an extended period of time.” The Federalist Society made textualism and originalism its brands. Its success is borne out by its 70,000 members and its association with all five Republican Supreme Court appointees. Justices Samuel Alito, Neil Gorsuch, Brett Kavanaugh, and Clarence Thomas remain active and visible in the group. Leadership in the local chapters has propelled numerous conservative lawyers to the federal courts of appeals.

As a result, justices finally align by party on controversial opinions. All the Republican justices are now more conservative than all the Democratic justices. Devins and Baum believe that this split has been driven, below the surface, by the divided political character of today’s elites. “To the extent that Justices act in ways that might draw favorable reactions from relevant elites, they are likely to do so unconsciously,” they write.

The authors reveal one unexpected finding about today’s elites. In earlier decades, liberal and conservative elites were closer on issues than the overall populations. Forty years ago, divisions were evident between economic and social conservatives. Today, they tell us, the social and economic conservative elites have united. Meanwhile, elite liberals have moved left, so that liberal and conservative elites are now more polarized than the general public. More surprising, at present more affluent and educated Republicans tend to be more conservative. The authors observe that “the most educated and affluent Republicans were the most conservative on issues that were likely to come before courts.” This is something new.

What it all means is unclear. Obviously, conservatives have much to be grateful for. The days of worry that the Supreme Court will declare capital punishment unconstitutional, for example, have ended for the foreseeable future, guaranteed. Also, the Supreme Court has recently ruled that the elected branches, with their working committees and agency expertise—rather than the courts—may direct the country’s security apparatus as they see fit. Additionally, Republican justices’ recent votes on nonmerit issues in abortion cases suggest that Roe v. Wade is on the way out. So, there is much to celebrate.

But worries remain. Originalism is not what is used to be. In District of Columbia v. Heller, in which the majority held gun ownership to be a personal right under the Second Amendment, both the majority and dissent relied on originalist arguments. Despite valiant efforts, the analysis and holding of Brown v. Board of Education desegregating schools cannot be defended as originalist, although those of Plessy v. Ferguson upholding the segregation of public facilities certainly can be. Currently, conservative elites are lobbying the court to overrule on originalist grounds Justice Scalia’s 1990 opinion in Employment Division v. Smith that limited religious freedom in using banned substances such as drugs. Apparently, originalism is a better slogan than coherent practice, and judicial restraint no longer has much appeal.

Moreover, the new alliance of economic and social conservatives outlined by Devins and Baum is surely overstated and inherently unstable. Elite law schools now host well-funded law-and-economics centers to critique the state’s economic interventions. The products of these centers are bound to rankle social conservatives opposed to open borders, for example. The agenda of the “conservative” Chamber of Commerce often conflicts with that of social conservatives.

Additionally, the relentless drumbeat of conservative elites on certain issues may be negatively influencing the Republican justices. Notably, last year’s Janus decision that overturned parts of a 41-year-old case allowing public unions to collect agency fees from unwilling nonmembers, is considered poorly reasoned even by many conservatives. And in 2005, the conservative dissenters did not distinguish themselves in Kelo v. New London, in which the majority upheld the city’s use of eminent domain. Still, the authors have presented us with a useful analysis, and perhaps a warning to justices to enjoy the accolades but to beware being swept off their feet.

[The Company They Keep: How Partisan Divisions Came to the Supreme Court by Neal Devins and Lawrence Baum (Oxford: Oxford University Press) $29.95]