Yesterday, the Attorney General of Massachusetts filed a lawsuit challenging DOMA.  It’s the third challenge filed in the last six months and for those of you ready to throw up your hands in confusion, don’t. Attorney General Martha Coakley has one of the best arguments yet.

The chief complaint in the brief filed yesterday afternoon is that DOMA, by limiting Massachusetts’ right to include same-sex spouses in Medicaid and bury same-sex spouses in a veteran cemetery as well as other federally funded programs that operate within the state, infringes on the state’s sovereign jurisdiction over marriage rights and definition.

The brilliance of this argument is that it takes the state’s rights approach, beloved by many conservative activists, legislators and litigators, and turns it around for the benefit of the more liberal among us.

If one opposes Coakley’s argument because it would weaken DOMA, then they also weaken state’s rights over marriage and that could benefit same-sex couples in the long run if the federal government ever gets around to imposing equal treatment for LGBT Americans.

If one capitulates to Coakley’s reasoning, DOMA is found to be unconstitutional and the entire Act is threatened.

It is a rock and a hard place if you will. Somewhat of a genius chess move.

The lawsuit also has the support of Senator John Kerry -  a champion for the rights of bi-national married same-sex couples – who argued against DOMA way back in 1996 in the Senate. He said then, “I oppose this legislation because not only is it meant to divide Americans, but it is fundamentally unconstitutional, regardless of what your views are. DOMA is unconstitutional. There is no single Member of the U.S. Senate who believes that it is within the Senate’s power to strip away the word or spirit of a constitutional clause by simple statute.”

Thirteen years later, we have our best shot at having a court agree with Kerry’s statement.

Coakley’s argument, alone, would likely only result in a reading down of DOMA’s application. So, DOMA wouldn’t apply to state-run federally funded programs that affect same-sex married spouses. But, Coakley’s lawsuit will likely be joined with the lawsuit filed by GLAD a few months ago and the two will attack DOMA’s application in state (Coakley) and DOMA’s application to many federal social programs that deny monetary benefits to same-sex spouses under current law.

Although success at the Supreme Court is still unlikely, both suits are carefully tailored to specific legal principles, they encourage a chipping away at DOMA’s reach and, if UAFA passes while these two suits are successful, DOMA will be all but undone.

It’s a rosy picture of the future. And that many wins are unlikely. But for today, we have some very clever allies in the fight for same-sex marriage.