To withstand heightened scrutiny, a legal distinction must substantially further an important government interest. The Justice Department, which announced two years ago that it would no longer defend DOMA and is now actively opposing it before the Supreme Court, concluded that the statute's ban on federal recognition of state-approved marriages between people of the same sex fails that test, since it affects marriage policy only "at the margin."
Likewise, says Solicitor General Donald Verrilli, Proposition 8 does not substantially advance any legitimate interest, since its impact is almost entirely symbolic. His brief strongly implies that the same argument invalidates the laws of seven other states (Delaware, Hawaii, Illinois, Nevada, New Jersey, Oregon and Rhode Island) that give same-sex couples "rights substantially similar to those available to married couples, yet still restrict marriage to opposite-sex couples."
Nine states and the District of Columbia recognize gay marriage.
So what about the remaining 33? It is pretty clear from Verrilli's discussion of the arguments for banning gay marriage that the administration does not think those states' laws could survive heightened scrutiny either.
But if the Supreme Court, which is scheduled to hear this case on March 26, adopts the administration's reasoning, the decision could discourage states from moving toward recognition of gay marriage, because doing so would make their laws less substantive and therefore less likely to be upheld. That would be a bizarre result, since it is hard to understand how giving gay couples none of the rights and privileges associated with marriage is less offensive to the principle of equal treatment under the law than giving them all those rights and privileges while calling their relationship something else.