When the Supreme Court came down with a major gay rights ruling last spring, Chief Justice John Roberts wrote his own dissent to emphasize one particular point.

The majority in United States v. Windsor had struck down a part of a federal law that denied federal benefits to legally married same sex couples. The Chief disagreed with the majority, but wanted to stress what he thought the case was not about: state bans on same sex marriage.

"I write only to highlight the limits of the majority's holding and reasoning today," he wrote. He stressed that the "court does not have before it" the question of whether states may ban same sex marriages.

Indeed, in a separate case that day, the Court held it lacked jurisdiction to consider California's ban on same sex marriage.

Fast forward to this past Wednesday. Federal district court Judge John Heyburn ruled that Kentucky's refusal to recognize legal same sex marriages violates the Constitution. And the judge cited Windsor.

Camilla Taylor, the marriage project national director at Lambda Legal, says change is happening with "lightning speed." She calls the Windsor decision a "game changer."

Eight months after the Supreme Court ruling in Windsor, there are more than 20 federal cases across the country in which plaintiffs are challenging either a state ban on same sex marriage, or a state's failure to recognize a marriage performed in another state.

As Heyburn put it: "Indeed, to date, all federal courts that have considered same sex marriage rights post-Windsor have ruled in favor of same sex marriage rights."

Not surprisingly, lawyers, state officials and judges do not all read Windsor the same way. Take one federal judge in Utah, for example, who ultimately struck down the state ban on gay marriage. In his opinion last December, U.S. District Judge Robert Shelby noted that the State focused on the portion of the Windsor opinion that emphasized federalism, and the state's historic authority to define marriage. But the plaintiffs (three gay and lesbian couples) argued that the Supreme Court had grounded its holding in the Due Process Clause of the Fifth Amendment, which protects an individual's right to liberty.

In the end, Judge Shelby sided with the plaintiffs. He said that "the important federalism concerns at issue here are nevertheless insufficient to save a state-law prohibition that denies the plaintiffs their rights to due process and equal protection under the law."

In the last few months, two federal judges have struck down gay marriage bans in Utah and Oklahoma, two federal courts in Virginia are currently hearing challenges, and just this week the attorney general of Nevada has reversed course and will no longer defend the state ban.

Ken Connelly , a lawyer for a group opposed to same sex marriage called Alliance Defending Freedom, thinks the courts that have used Windsor in part to strike down state marriage laws have "simply gotten it wrong, and ignored its holding."

"We are confident that on appeal these district court decisions will be overruled," he says.

"What the Supreme Court found unconstitutional with regard to the Defense of Marriage Act (DOMA) is that it represented the federal government deviating from its usual practice of accepting state definitions of marriage. But nothing in Windsor prohibits a state from continuing to define marriage as between a man and a woman. In fact, Windsor is full of assurances that the states retain that right."

But Lambda Legal's Taylor said, that Windsor "made clear the justifications cited by Congress for passing DOMA were illegitimate. Those same justifications were used by state legislatures in passing state marriage bans."

Taylor points to a decision made in Nevada last Monday night by state officials who said they could no longer defend the state's ban on gay marriage. The about face came after a panel of the 9th Circuit Court of Appeals ( in a different case) made it much more difficult for states -under the 9th Circuit's jurisdiction- to justify bans on same sex marriage. The majority in the case cited Windsor. "Windsor requires that heightened scrutiny be applied to equal protection claims involving sexual orientation," wrote Judge Stephen Reinhardt.

The ruling caused Attorney General Catherine Cortez Masto to tell the Court Monday night that under the new standard of review the State's argument "cannot withstand legal scrutiny."

Meanwhile, the 10th Circuit Court of Appeals is poised to hear arguments this spring concerning the Utah and Oklahoma state bans that were struck down by the Courts.

In Virginia, the American Civil Liberties Union and other groups have filed a federal class action lawsuit seeking the freedom to marry for all same-sex couples in Virginia . In another part of the state lawyers Ted Olson and David Boies were in Court on Feb. 4 arguing the state ban should fall. Virginia's Attorney General Mark Herring is refusing to defend the ban.

Instead, the Virginia ban was defended in court by lawyer Austin R. Nimocks of Alliance Defending Freedom. He represents Michelle McQuigg, the clerk of the circuit court in Prince William County. Nimocks told Judge Arenda Wright Allen of the United States District Court for the Eastern District of Virginia , "We have marriage laws in society because we have children, not because we have adults." He said it is "reasonable and constitutional" for Virginians to accept "that it is better - all other things being equal - for children to grow up with both a mother and a father."

When former Republican Attorney General Kenneth T. Cuccinelli II, Herring's predecessor, was in office, he argued in support of the ban and in support of the federalism language present in Windsor. In briefs he wrote, "Where a state has defined marriage in the first, traditional, conjugal fashion since its original settlement in 1607, the Windsor analytic framework is simply unavailing in support of plaintiffs."

Justice Anthony Kennedy, the author of the majority opinion in Windsor, said in his last sentence that the opinion "and its holding" were confined to those lawfully married in their states. But in a scathing dissent, Justice Antonin Scalia, joined in full by Justice Clarence Thomas, said it took "real cheek" for the majority to "assure us, as it is going out the door, that a constitutional requirement to give formal recognition to same sex marriage is not at issue here."

So far, lower court judges seem to be agreeing with Scalia's conclusion.