If Judge Neil Gorsuch is confirmed as the next Supreme Court justice, he would play a decisive role in the future of same-sex marriage in the United States. The Court held in its 2015 Obergefell decision that there is a nationwide right of same-sex couples to marry. But no Supreme Court decision is written in stone. Gorsuch’s statements on the issue in his 2004 Oxford University dissertation for his Doctorate in Philosophy reveal that he thought it obvious that the United States Constitution did not protect a right to same-sex marriage. If he still holds this view, he could join forces with other justices to reverse the Court’s protection of this right.

In order to understand why Gorsuch’s statements are potentially problematic for the future of same-sex marriage, we first have to understand the connection between the Constitution’s protection of that right and the legal doctrine that paved the way for it—the idea that the Constitution protects individual choice in matters of intimacy for gay and straight people alike. Gorsuch is critical of this legal doctrine, sometimes referred to as the right to privacy or autonomy.

The right to make choices in intimate matters is based in Griswold v. Connecticut (1965), a case holding that married couples have the right to use contraception. This right was later broadened by the Court to include non-married couples.

In Planned Parenthood v. Casey (1992) the Court extended the Constitution’s guarantee of autonomy in intimate matters to include abortion, arguing that abortion, like contraception, was a personal decision. As Justices O’Connor, Kennedy and Souter wrote in their opinion, “Our law affords constitutional protection to personal decisions relating to marriage, procreation, contraception, family relationships, child rearing, and education.” They argue that “these matters, involving the most intimate and personal choices a person may make in a lifetime, choices central to personal dignity and autonomy, are central to the liberty protected by the Fourteenth Amendment. At the heart of liberty is the right to define one’s own concept of existence, of meaning, of the universe, and of the mystery of human life.”

In later decisions, the Court would use this idea of a privacy guarantee to defend gay rights. In its 2003 decision in Lawrence v. Texas, the Court invoked the liberty provision of the Due Process Clause to strike down a Texas law banning “homosexual conduct.” The Due Process Clause of the Fourteenth Amendment provides that no state “shall . . . deprive any person of life, liberty, or property, without due process of law.” Texas had unconstitutionally deprived its gay citizens of their liberty by prohibiting them from having sexual relations. The opinion stressed that the Texas law conflicted with the right of all adults, gay or straight, to have personal choice in matters of consensual sexual relations. The Lawrence decision also helped lay the groundwork for the Court’s later holding in Obergefell that the right to marriage is fundamental and that same-sex couples cannot be excluded from it.

When Gorsuch wrote a dissertation to fulfill his PhD requirements at Oxford, his dissertation advisor, who deeply influenced his work, was John Finnis. Finnis, a prominent law professor at Oxford and Notre Dame, is a critic of the Court’s decisions about choice in intimate matters, specifically its support for abortion rights and same-sex marriage. Finnis rejects the idea that the state should protect individuals’ ability to make autonomous choices in these areas. Instead, his natural law theory calls for the state to promote a list of “basic goods.” He argues that such a philosophy is incompatible with same-sex marriage or abortion, both of which he thinks should be prohibited by law. Indeed, he refers to heterosexual marriage as the only “real” kind of marriage.

Gorsuch invokes Finnis’ natural law framework in his dissertation, which focuses on the legal debate around physician-assisted suicide. Stressing the importance of “human life as a basic good,” Gorsuch argues that there is no constitutional right to physician-assisted suicide. Instead, he claims that the government can protect the basic good of life by preventing the seriously ill and their doctors from making the choice to end it. He writes, “ruling out a ‘bad choice’ does not necessarily evince disrespect for the chooser, but for the choice he or she made; after all, parents punish children who make bad choices, not because they disdain them, but because they love them and do not wish to see them make bad decisions.”

Gorsuch’s criticism of choice in the context of assisted suicide includes a broader attack on the idea of a constitutional right to autonomy in intimate personal matters. This attack focuses on the Court’s Casey decision, critiquing the opinion from Casey quoted above and negatively referencing same-sex marriage. Casey upheld the right to abortion and confirmed the Constitution’s protection of individual autonomy in intimate personal matters. Gorsuch argues that recognizing this right to autonomy would mean that the state would have to allow every type of voluntary adult intimacy, even those he thinks should clearly be illegal. He writes that Casey’s invocation of a constitutional right to personal choice is “open to question on the ground that it proves too much.” He continues,

If the Constitution protects as a fundamental liberty interest “intimate” or “personal” decisions, the Court arguably would have to support future autonomy-based constitutional challenges to laws banning any private consensual act of any significance to the participants in defining their “own concept of existence.” As Judge O’Scannlain queried in dissent in the Ninth Circuit’s proceedings: “If physician-assisted suicide is protected ‘intimate and personal choice,’ why aren’t polygamy, consensual duels, prostitution, and, indeed, the use of illicit drugs?” Justice Scalia raised much the same question in Lawrence, contending that “State laws against bigamy, gay marriage, adult incest, prostitution, masturbation, adultery, fornication, bestiality, and obscenity” are all at risk if we take seriously what Justice Scalia derided as Casey’s “famed sweet-mystery-of-life passage.”

In the quoted passage, Gorsuch marshals evidence against Casey’s embrace of a broad right to privacy because that right threatens his strong opposition to assisted suicide. The gist of the paragraph is that the Casey decision is open to question because it would allow for a long list of rights that he thinks should clearly not protected by the Constitution. He cites Justice Scalia to suggest that gay marriage, like bestiality, should be included on this list.

Part of what is concerning here is the conflation of gay marriage, which is central to the family life of gay and lesbian people, and practices like bestiality, which should be prohibited. In criticizing the doctrines of autonomy and privacy, Scalia places gay marriage and bestiality in the same category, ignoring the obvious distinctions. Gorsuch, in turn, fails to distance himself from this reasoning.

In a book based on his dissertation, The Future of Assisted Suicide and Euthanasia, published in 2006, Gorsuch moves this Scalia quote to a footnote. Did he do so because he has changed his mind and wants to differentiate his view from Scalia’s? Or did he wish to make opaque his true opinion about the topic, revealed in his dissertation? The confirmation hearings are the place to ask.

Gorsuch’s dissertation was written before the Court’s 2015 decision in Obergefell. As an appellate judge, Gorsuch is bound to follow the holdings of the Supreme Court. But as a Supreme Court justice, he would be free to participate in overturning Obergefell and abolishing this right. The Obergefell decision rested on a rationale of marriage as a fundamental right, an argument that goes beyond the choice rationale Gorsuch addressed. Therefore, Gorsuch should also be asked whether this argument led him to change his position on gay marriage. If he refuses to answer, we are left only with his negative comments from the dissertation to help us discern whether he would work to revoke the right of same-sex marriage. Given his criticism of personal autonomy protections and his invocation of Scalia’s dissent in Lawrence, he should also be asked whether he would overturn the Lawrence decision, a move that could eventually open the door to new laws against gay sex.

If Judge Gorsuch had been a Supreme Court justice during the Lawrence and Obergefell cases, it is quite possible that he would have decided these cases differently. However, this does not automatically mean that he would vote to overturn them if he were to join the Court now. After all, some justices may leave decisions in place out of respect for precedent rather than whole-hearted agreement. Gorsuch acknowledges, for instance, that Casey’s holding is based in “stare decisis,” the concept justices invoke to acknowledge the legal authority of previous rulings. But we have reason to doubt that he would simply defer to precedent as a Supreme Court Justice. Gorsuch subscribes to the constitutional theory of originalism, whose proponents stress the original meaning of the Constitution as a legal authority over precedent when the two conflict.

Gorsuch’s affinity with the views of his adviser Finnis on natural law, his approving citation of Scalia’s views on gay marriage, and his skepticism of the Court’s jurisprudence on the right to chose in matters of personal intimacy all suggest that he might vote to reverse the decision protecting same-sex marriage. Defenders of gay rights have reason to worry that he would roll back the clock on this important issue, and senators should use the upcoming confirmation hearings to find out from Gorsuch exactly where he stands.

Brettschneider is Professor of Political Science at Brown University and the author of When the State Speaks, What Should It Say? How Democracies Can Protect Expression and Promote Equality. He holds a Ph.D. in Politics from Princeton University and a law degree from Stanford Law School.

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