Michigan's public employers may now choose to offer benefits, such as health insurance, to same-sex domestic partners.
Five gay couples sued the state regarding government employee benefits.
U.S. District Judge David Lawson cited last week's Supreme Court ruling overturning some parts of the federal Defense of Marriage Act, to strike down a Michigan law barring public employers from extending benefits to same-sex partners.
At this point, the judge's ruling is only an injunction that lifts the state's ban on public employer's providing benefits to gay partners. But some say Lawson's strong language indicates he may strike the law down for good.
"It is hard to argue with a straight face that the primary purpose - indeed perhaps the sole purpose - of the statute is other than to deny health benefits to the same-sex partners of public employees," Lawson wrote in his ruling. "But that can never be a legitimate government purpose."
Michigan's constitution defines marriage as between one man and one woman.