The Constitution won't interpret itself. Ketanji Brown Jackson owes us an answer on her judicial philosophy.

Supreme Court justices need more than a commitment to impartiality. Even an impartial judge must interpret the law. That requires a judicial philosophy.

Scott Douglas Gerber
Opinion contributor

Judge Ketanji Brown Jackson testified during her Senate confirmation hearing that her judicial "philosophy" is her judicial "methodology," and that her judicial methodology is to be neutral, to understand the facts and to interpret the law. 

That testimony was problematic.

Judicial philosophy is the way a judge understands and interprets the law. Different theories of interpretation sometimes lead to different answers about the meaning of the Constitution, which is why it is important to know what a Supreme Court nominee's judicial philosophy is.

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All judges, including Supreme Court justices, are required to interpret three categories of law: the Constitution, statutes and case precedents. A judicial philosophy is necessary in every category.

Our laws pose inescapable questions 

The most important type of law that a Supreme Court justice must interpret is the Constitution. Significantly, the Constitution is not self-interpreting. Understanding what America’s fundamental law means presupposes a judicial philosophy and poses inescapable questions of substantive value choices.

Judge Ketanji Brown Jackson at her Supreme Court nomination hearing on March 21, 2022.

Scholars have identified six principal theories for interpreting the Constitution:

►Textualism focuses on the language of the Constitution. Justice Hugo Black was the Supreme Court's most committed textualist.

►Originalism is concerned with understanding what the Constitution's text meant at the time it was written. Justice Antonin Scalia was the most celebrated originalist.

►Structuralism is a method of inference from the structures and relationships created by the Constitution. John Marshall, the "great chief justice," was a structuralist.

Doctrinalism is analysis based upon the application of precedent. John Roberts, the current chief justice, is a doctrinalist.

►Prudentialism balances the interests and values surrounding a case. Stephen Breyer, the justice whom Jackson has been nominated to succeed, is a prudentialist.

►Moralism decides cases in light of the ethos of the Constitution. Justice Thurgood Marshall, who argued and won Brown v. Board of Education as a civil rights lawyer, was a moralist.

Different theories can lead to different answers. For example, a textualist approach would conclude that the Constitution does not guarantee an individual’s right to privacy – what has come to be known as "personal autonomy" – because the word "privacy" does not appear in the Constitution, whereas a moralist would likely conclude that privacy is protected by the Constitution because individual liberty is central to the Constitution's ethos.

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Supreme Court nominee Ketanji Brown Jackson answers questions before the Senate Judiciary Committee during her confirmation hearing on March 22, 2022.

The aforementioned theories of constitutional interpretation are not mutually exclusive, and a specific Supreme Court justice sometimes employs different theories in different cases. But each case requires more of a judge than a professed commitment to impartiality and to the application of the facts to the law. Even an impartial judge must interpret the law before he or she can apply the facts of the case to the law. And that requires a judicial philosophy about legal interpretation.

Judicial theories and values differ

A judicial philosophy is also necessary for interpreting statutes. Not surprisingly, there are different theories of statutory interpretation. The two principal approaches are the textualist approach that Scalia championed and the purposive approach favored by Breyer.

Scalia, who coauthored a book in 2012 titled "Reading Law: The Interpretation of Legal Texts," famously insisted that legislative history was irrelevant to the meaning of a statute and that judges should avoid invoking it. According to Scalia, a judge should focus solely on the text of the statute as illuminated by time-honored textual canons of construction, such as "ejusdem generis" (which means of the same kind, class or nature) and "expressio unius est exclusio alterius" (which means the express mention of one thing excludes all others).

Supreme Court Justice Stephen Breyer holds up a copy of the U.S. Constitution as he announces his retirement on Jan. 27, 2022.

Breyer, in contrast, maintains that the purpose for which a statute is enacted is of primary importance when interpreting it. Breyer wrote that a purposivist approach to statutory interpretation incorporates "widely shared substantive values, such as helping to achieve justice by interpreting the law in accordance with the 'reasonable expectations' of those to whom it applies."

Judges have (and need) a philosophical lens

A judge needs a philosophy for interpreting precedent. The Mississippi case on the Supreme Court's current docket about whether the Roe v. Wade and Planned Parenthood v. Casey abortion precedents should be overruled illustrates how important it is for a justice to a have a philosophy about precedent.

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Lawyers and judges who argue that the court's pro-choice precedents should not be overruled insist that every argument against Roe was rejected in the court’s 1992 Casey decision, and that nothing has changed since then except the composition of the court. They also emphasize that adherence to Roe and Casey is important to reaffirm the court's commitment to stare decisis and the rule of law, and that preserving respect for the rule of law is an elemental judicial task.

Scott Douglas Gerber is a law professor at Ohio Northern University and an associated scholar at Brown University’s Political Theory Project. His nine books include "A Distinct Judicial Power: The Origins of an Independent Judiciary, 1606-1787."

Those who want Roe and Casey overruled maintain that both were "egregiously" wrong, and that the Constitution's text trumps judicial decisions that are inconsistent with the Constitution. As one conservative law professor succinctly put it, "The doctrine of stare decisis cannot properly be understood or applied in such fashion as to permit the justices deliberately to render a decision contrary to the correct reading of the Constitution."

Jackson came across during her confirmation hearing as a bright and well-credentialed judge, and as a nice person. But a Supreme Court justice needs a judicial philosophy. Jackson should tell the American people what hers is.

Scott Douglas Gerber is a law professor at Ohio Northern University and an associated scholar at Brown University’s Political Theory Project. His nine books include "A Distinct Judicial Power: The Origins of an Independent Judiciary, 1606-1787."