Adam White has an excellent essay on the Liberty Law Blog discussing Justice Clarence Thomas’s distinctive approach to the Constitution entitled,  “Just, Wise, and Constitutional”: Justice Thomas’s Legacy in Law and Politics. He begins by emphasizing what knowledgeable observers of the Court have long since come to realize: Contrary to the knee-jerk reactions to him during his early years on the Court, Justice Thomas is no “clone” of Justice Scalia:

Before delving into Thomas’s and Scalia’s fundamental differences, one must pause to relish the irony that the Left so casually assumed, two decades ago, that the newly appointed Thomas would follow Scalia in all things. That’s no exaggeration. The Washington Post’s Mary McGrory asserted in 1992: “Thomas has come on as Scalia’s puppet.” Linda Greenhouse, of the New York Times, was gentler, but no less prejudiced, when she calledScalia Thomas’s “apparent mentor.” Newsweek trafficked in outright conspiracy theory: “Not only is Scalia an aggressive and articulate proselytizer but one of his former law clerks now works for Thomas. The clerk, Newsweek has learned, exerts considerable influence over the rookie justice.” All told, the conventional wisdom was best reflected by an ACLU official, who complained that “Thomas and Scalia are one person with two votes.”

Thomas’s prejudiced critics were not just wrong—they got things precisely backward. From the very beginning, his iconoclasm inspired Scalia to change some of his own votes. InSupreme Conflict (2007), Jan Crawford described how the newly appointed Thomas not only charted his own path, but also convinced Scalia and other justices to change their minds and follow his lead. “After Thomas’s very first conference,” Crawford writes, “Scalia changed his mind” in Foucha v. Louisiana, a controversial civil-detention case, and “on several other occasions that term.” Chief Justice Rehnquist and Justice Kennedy also changed their minds, persuaded by the rookie justice in Foucha. “But,” Crawford adds, “these maneuvers were unknown to outsiders and Court watchers.”

How are they different? For example,

On the bench, this fundamental difference between Thomas and Scalia is clearest in their discussions of the Fourteenth Amendment’s privileges or immunities clause. In McDonald v. City of Chicago, the second of the Court’s recent gun-rights cases, Thomas’s concurring opinion (for himself alone) not only set forth a thorough defense of the clause’s protection of enumerated constitutional rights against state infringement, but also opened the door to judicial protection of constitutional rights not expressly specified within the generally protection of the Fourteenth Amendment’s privileges or immunities clause:

The mere fact that the Clause does not expressly list the rights it protects does not render it incapable of principled judicial application. The Constitution contains many provisions that require an examination of more than just constitutional text to determine whether a particular act is within Congress’ power or is otherwise prohibited. … To be sure, interpreting the Privileges or Immunities Clause may produce hard questions. But they will have the advantage of being questions the Constitution asks us to answer.

White emphasizes the degree to which, unlike Justice Scalia, Justice Thomas’s reading of the Constitution is informed by the Declaration of Independence.

Justice Thomas’s most significant contribution to constitutional law goes to first principles—namely, the first principles underlying the American nation. According to Thomas . . . , the fundamental principles of natural law set forth in the Declaration of Independence breathe life into the Constitution’s structures and procedures, and find protection in the Bill of Rights. . . .

Thomas’s unflinching embrace of natural law was evident from the very beginning—not just in his Supreme Court opinions, or even at his confirmation hearing, but in the speeches that brought him to prominence as chairman of the Equal Employment Opportunity Commission.

Addressing the Heritage Foundation in 1987, then-EEOC Chairman Thomas criticized “the post-Reagan Republican Party” for lacking a principled message that would attract black Americans. Specifically, he challenged conservatives to “begin the search for standards and principles with the self-evident truths of the Declaration,” urging that “we must attempt to recover the moral horizons of [Abraham Lincoln’s] speeches. . . . Without such a notion of natural law, the entire American political tradition, from Washington to Lincoln, from Jefferson to Martin Luther King, would be unintelligible.”

Over the next year, Chairman Thomas went still further, tying those political themes to expressly constitutional ones. In a 1987 article entitled “Toward a ‘Plain Reading’ of the Constitution—The Declaration of Independence in Constitutional Interpretation,” Thomas wrote that “the first principles of equality and liberty should inspire our political and constitutional thinking,” and that such “principled jurisprudence” would “pose a major alternative to the cynical rejection of ‘the laws of nature and of nature’s God’ from jurisprudence.”. . .

Then, at the Federalist Society’s 1988 national symposium, Chairman Thomas tied the Declaration’s natural law principles to the Fourteenth Amendment’s “privileges or immunities” clause. And in so doing, he challenged the then-dominant view among conservatives that the courts should not enforce rights not specifically protected by the Constitution:

The expression of unenumerated rights today makes conservatives nervous, while at the same time gladdening the hearts of liberals. I would like to take a different approach . . . The best defense of limited government, of the separation of powers, and of the judicial restraint that flows from the commitment of limited government, is the higher law political philosophy of the Founding Fathers. Contrary to the worst fears of my conservative allies, such a view is far from being a license for unlimited government and a roving judiciary. . . . The higher-law background of the American Constitution, whether explicitly invoked or not, provides the only firm basis for a just, wise, and constitutional decision.

White concludes by connecting Justice Thomas’s approach to the Constitution with the recent movement among “constitutional conservatives” towards judicial engagement.

Today, Thomas’s calls for a constitutionalism informed by natural law finds echoes in the work of libertarian lawyers and scholars such as Randy Barnett and Clark Neily (not to mention an increasingly libertarian George Will), who call for “judicial engagement” to enforce rights more aggressively in court than would some of the more traditional originalists, who tend to favor “judicial restraint.” At the same time, Barnett calls for a “popular sovereignty” that directs constitutional argument not just to the courts, but to the public at large. If their promotion of constitutional law infused with fundamental liberty reflects Justice Thomas’s own approach, then it is all the more fitting that they are learning to pursue those aims through the very means that Thomas himself urged a quarter-century ago.

I would emphasize that the protection of the background natural rights “retained by the people” to which both the Declaration and the Ninth Amendment refers do not require judges to identify and give enhanced protection to some special set of unenumerated rights. Instead, they need to focus not on right but on the proper scope of governmental powers by holding the federal government to its enumerated powers and state governments to their police power to protect, for example, the health and safety of the public. At both state and federal levels, this means asking whether restrictions on liberty were enacted in good faith, as opposed to, say, helping out some crony capitalists.

But there is a whole lot more Adam White’s essay than is reflected in these excerpts. Read the whole thing here.