Not surprisingly, the shift has moved in tandem with public opinion. A recent Washington Post-ABC News poll found that support for legal gay marriage has hit an all-time high at 58 percent, up 21 points over the last decade alone.
The reason behind that shift came up during Wednesday's hearing. Chief Justice John Roberts Jr. suggested that it was at least partly the result of a long-term lobbying campaign by proponents. "As far as I can tell, political figures are falling over themselves to endorse your side of the case," he said to Roberta Kaplan, the lawyer arguing against DOMA.
Kaplan countered that gays historically have not had much political power. And she argued that the change "comes from a moral understanding today that gay people are no different, and that gay married couples' relationships are not significantly different from the relationships of straight married people."
As the case has moved through the courts, gay rights activists have repeatedly invoked the 1996 House judiciary report to show that "the reason it was passed was to discriminate against gays and lesbians," said Brian Moulton, legal director for the Human Rights Campaign, a gay advocacy group.
In response to Kagan, Clement allowed that "a couple of legislators may have had an improper motive." He said there were other reasons, including "democratic self-governance," that were also cited and that should justify upholding the law.
Roberts appeared skeptical that prejudice played a major role. "That was the view of the 84 senators who voted in favor of it and the president who signed it?" he asked Solicitor General Anthony Verrilli. "They were motivated by animus?"
No, Verrilli replied. "But whatever the explanation, whether it's animus, whether it's that more subtle, more unthinking . . . kind of discrimination, [DOMA] is discrimination," he said.