(CN) - The 2nd Circuit on Thursday became the second federal appeals court to strike down the Defense of Marriage Act as an unconstitutional violation of equal protection.
A three-judge panel upheld a federal judge's finding that the law, which defines marriage as the union of one man and one woman, tramples on the rights of same-sex couples by denying them equal treatment.
Chief Judge Dennis Jacobs said that because the law's "classification of same-sex spouses was not substantially related to an important government interest," the 1996 law "violates equal protection and is therefore unconstitutional."
The ruling is a victory for 83-year-old Edith Schlain Windsor, who sued the government in 2010 after she was forced to pay federal estate tax when her wife, Thea Spyer, passed away in 2009.
Federal law provides an estate-tax exemption on spousal inheritance, but Windsor did not qualify for the exemption under DOMA.
Windsor and Spyer married each other in Canada and another jurisdiction where same-sex marriage is legal, and had been together in New York since 1963.
With Thursday's ruling, the 2nd Circuit in Manhattan joins its sister circuit in Boston, which held in May that "Congress' denial of federal benefits to same-sex couples ... has not been adequately supported by any permissible federal interest."
In 2011, the Obama administration told Congress it would no longer defend DOMA.
And last month, Justice Ruth Bader Ginsburg indicated that the Supreme Court will likely rule on DOMA within the year.
"I think it's most likely that we will have that issue before the court toward the end of the current term," she said during a Q-and-A session at the University of Colorado on Sept. 19.
Since Congress passed DOMA in 1996, six states and the District of Columbia have legalized gay marriage, while 31 states have passed amendments to ban it.
Federal judges nationwide have rejected the law as unconstitutional over the past few years.
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