DOMA is the Defense of Marriage Act. Passed in 1996, before anyone even dreamed that gay couples could marry, its clause 3 forbids the Federal Government from recognizing legally married gay couples. Which is why my marriage is non-existant to the Fed, leading to a pattern of insults large and small from taxes to customs to pensions. Our attorney and accountant make money of this. We are expected to lie to the IRS (it's the law) and we've been routinely insulted by customs agents.
In the latest case, legally married Edie Windsor protested the fact that the IRS charged her wife's estate over $300,000 dollars in estate taxes that would not have been charged had she been married to a man. Edie and Thea were together for 44 years.
The Federal District Court in NY found no reason why Edie's and Thea's marriage should be so disadvantaged or how this disadvantage would somehow promote straight couples marrying or bearing children.
That brings to 5 the cases that have found DOMA unconstitutional. The furthest along is in the 1st circuit (where the 1st circuit appeals court just found DOMA unconstitutional). There are 3 cases in CA (on appeal to the 9th). The current case, if appealed, will go to the second circuit.
This is headed to the Supreme Court, for sure.