What exactly Supreme Court nominee Neil Gorsuch’s stance on LGBT rights is has remained somewhat of a mystery until this point, although many have had their guesses. But now an article published by TIME over the weekend has revealed Gorsuch’s been an opponent of same-sex marriage since at least 2004.

In his 2004 PhD. Oxford University dissertation, Gorsuch outlined his belief that the U.S. Constitution does not support the right of marriage for same-sex couples.

Brown University professor of political science Corey Brettschneider, who wrote the TIME article, noted that “Gorsuch’s statements…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.”

Gorsuch is a “textualist,” or “originalist”, meaning he believes the Constitution is not a living document. He does not see it as being subject to interpretation, and therefore there is no right to privacy since the word does not exist in the Constitution.

Brettschneider also believes that Gorsuch’s dissertation advisor, John Finnis, “deeply influenced his work”. On Finnis he wrote:

Gorsuch’s confirmation hearings began today.

Watch Judge Neil Gorsuch’s Senate confirmation hearing LIVE, below: