The Second U.S. Circuit Court of Appeals in New York ruled today that the Defense of Marriage Act, more specifically Section 3— the federal definition of marriage between one man and one woman—violates equal protection and is therefore unconstitutional. Today's ruling makes the Second U.S. Circuit Court of Appeals the second federal court to hold DOMA unconstitutional. Today's decision hinges on Section 3 of DOMA, the part of the legislation which defines marriage. Section 3 states:

In determining the meaning of any Act of Congress, or of any ruling, regulation, or interpretation of the various administrative bureaus and agencies of the United States, the word `marriage' means only a legal union between one man and one woman as husband and wife, and the word `spouse' refers only to a person of the opposite sex who is a husband or a wife.''

"The United States, the defendant, is a nominal appellant ... [W]e conclude that Section 3 of the defense of Marriage Act violates equal protection and is therefore unconstitutional," reads the majority opinion (found here). And more specifically, the decision reads: 

Instead we conclude that review of Section 3 of DOMA requires heightened scrutiny.The Supreme Court uses certain factors to decide whether a new classification qualifies as a quasi-suspect class. They include: A) whether the class has been historically “subjected to discrimination,”; B) whether the class has a defining characteristic that “frequently bears [a] relation to ability to perform or contribute to society,” C) whether the class exhibits “obvious, immutable, or distinguishing characteristics that define them as a discrete group;” and D) whether the class is “a minority or politically powerless."

"This is a really big deal. [Chief Judge] Jacobs is not simply saying that DOMA imposes unique and unconstitutional burdens on gay couples, he is saying that any attempt by government to discriminate against gay people must have an 'exceedingly persuasive' justification," writes Think Progress's Ian Millhiser, who notes that this is the same "skeptical standard afforded to laws that discriminate against women." Quite simply, if discriminating against gay men and women is being considered in the same light as gender discrimination, it would make then make the reality of the Supreme Court striking down DOMA all the more likely if (or, at this point, when) they take up the cases. The Supreme Court appeals are currently pending.