Wikipedia said:
Chief Justice John Roberts wrote a dissenting opinion, which was joined by Justices Scalia and Thomas. Roberts accepted substantive due process, by which fundamental rights are protected through the Due Process Clause, but warned it has been misused over time to expand perceived fundamental rights, particularly in Dred Scott v. Sandford and Lochner v. New York.[129] Roberts stated that no prior decision had changed the core component of marriage, that it be between one man and one woman; consequently, same-sex marriage bans did not violate the Due Process Clause.[130] Roberts also rejected the notion that same-sex marriage bans violated a right to privacy, because they involved no government intrusion or subsequent punishment.[131] Addressing the Equal Protection Clause, Roberts stated that same-sex marriage bans did not violate the clause because they were rationally related to a governmental interest: preserving the traditional definition of marriage.[132]
More generally, Roberts stated that marriage, which he proposed had always had a "universal definition" as "the union of a man and a woman", arose to ensure successful childrearing.[133] Roberts criticized the majority opinion for relying on moral convictions rather than a constitutional basis, and for expanding fundamental rights without caution or regard for history.[134] He also suggested the majority opinion could be used to expand marriage to include legalized polygamy.[135] Roberts chided the majority for overriding the democratic process and for using the judiciary in a way that was not originally intended.[136] According to Roberts, supporters of same-sex marriage cannot win "true acceptance" for their side because the debate has now been closed.[137] Roberts also suggested the majority's opinion will ultimately lead to consequences for religious liberty, and he found the Court's language unfairly attacks opponents of same-sex marriage.[138]