When Barack Obama proved unwilling to hound an octogenarian widow for a tax bill she never should have been charged, House Speaker John Boehner proved more than willing to take up the task—even at a cost to taxpayers of far more than the money she owed.

That’s how the case of Edith Windsor versus the United States of America came to be argued before the Second Circuit Court of Appeals in Manhattan last September--and now, six months later, in front of the United States Supreme Court. The New York hearing was a strange one, where the defendant, backed by the Democratic president, argued that she should owe $360,000 less in taxes than the IRS has collected, while the appellant, working on behalf of the Republican Speaker, argued she should foot the bill.

Legally, the case is about the constitutionality of Section 3 of the Defense of Marriage Act of 1996. In practical terms, it’s about a good chunk of money that Windsor would like to get back—and the freedom for consenting adults to behave as they wish without being financially penalized by the government.

With homosexuality involved, the G.O.P. has assumed the contorted position of demanding an elderly woman pay what in other circumstances they might deem a death tax. At the same time, the federal judges argued with the lawyer from the Justice Department about which side of the courtroom he should have been arguing from.

Listening on the other side of the court was Edith Windsor herself, a spry 83-year-old with bright eyes and a pixie-like smile. In 2007, she married her companion of 42 years, Thea Spyer, in Canada. The couple had wanted to wait to get married until it was legal to do so in their home state of New York, but as Spyer’s health declined due to multiple sclerosis, they wed north of the border shortly before Spyer died in 2009.

While New York State had not yet legalized same-sex marriage (it did in 2011), it did recognize same-sex marriages that had been legally performed in other jurisdictions. So when Spyer passed away, Windsor was treated as her spouse under New York State law, and she was allowed to inherit what her spouse had left her without being taxed, the same as any heterosexual surviving spouse.

But under federal law, it was a very different story. Under DOMA, the United States government does not recognize marriages between members of the same gender, and thus will not confer any legal spousal benefits to homosexuals, including the ability to sponsor a foreign partner, file taxes jointly, or bequeath property without taxation. The Republican Party, so often in thrall to Grover Norquist and his no-tax increase pledge, proved more than willing to hit homosexuals with huge tax bills. (While New York State is now one of six states, along with Washington D.C., where same-sex marriages are legally performed, none of those unions are formally recognized by the federal government—so if the couple had been married at home rather than in Canada, it would not have made any different on her federal tax bill after losing her spouse, or to her legal position.)

Windsor found this out the hard way when Spyer left her half of the wealth (mostly property) the couple had amassed jointly over their lifetime together. But for purposes of federal taxation, Syper and Windsor were nothing more than strangers, meaning the IRS demanded Windsor shell out more than a third of a million dollars in inheritance taxes that a straight widow would not have paid.

To rectify this gross injustice, Windsor sued the United States in November 2010, and her legal team (represented Thursday in court by Roberta Kaplan of Paul, Weiss, Rifkind, Wharton & Garrison) argued that Section 3 of DOMA was unconstitutional. This June, a federal district court agreed with them—one of five such district-court losses the anti-gay law has suffered—handing Windsor her first legal victory.

In between when Windsor filed suit and the district court decision, Obama and Attorney General Eric Holder decided in February of 2011 that DOMA was unconstitutional, and they the Justice department would no longer defend the law in court as such. Incensed that the executive branch wasn’t willing to push for the law—which seems on the face of it to deprive homosexuals of the right to enter into the same contracts as heterosexuals, and thus of equal protection under the law—House Speaker John Boehner exercised his right in such circumstances to do so and instructed the Bipartisan Legal Advisory Group (BLAG) to defend the law in court.

Reportedly, Boehner has already spent twice as much on legal fees as he’s trying to collect from Windsor.

As Republicans treat the case as nothing less than a threat to the rule of law, Kaplan told the judges that the case before them is a narrow one, rather than a wide-reaching attempt to redefine marriage. But Windsor herself told me last summer that she hopes her case is the one that finally results in all consenting adults sharing the right to marry in America. (Her case is one of several DOMA-related ones moving their way up the appeals process toward a likely Supreme Court showdown, along with a challenge to California’s Proposition 8 that doesn’t directly involve DOMA.)

“I want everybody to profit from this!” she said after she won in district court.

On the appellate side, sitting next to conservative legal star Paul Clement (who made the case against Obamacare before the Supreme Court), was Stuart Delery, the openly gay Acting Assistant Attorney General who had to explain to the Court why the Department of Justice had stopped defending DOMA.

“In my day, if you won, you didn’t appeal,” Chief Judge Dennis Jacobs said to Delery when he first tried to speak, questioning why the DOJ was appealing the case Windsor has won, even though by not defending the law it was in practice siding with her.

Clement, meanwhile, referred repeatedly to New York State’s same-sex marriage law in almost glowing terms, arguing the law, passed by the legislature and signed by the governor, showed that the states were free to offer a more expansive definition of marriage than DOMA’s. If gays and lesbians want to change marriage federally, he argued, they could do so by using political power to press Congress to overturn DOMA, just as they had in New York, rather than through the courts. Over 100 lawmakers have co-sponsored legislation to change the law, he noted, including some of its 1996 sponsors.

In arguments, Jacobs seemed sympathetic to the idea that the court wasn’t the appropriate venue, telling Delery: “Your presence is like an argument against your argument.” Inside the court, the phrase “your presence” came across as if the judge were speaking directly to Delery as an out gay attorney, as well as a representative of the Justice Department.

After the hearing, Kaplan took issue with the idea that gay or lesbian people now wield significant political power, noting that more than half of the states have explicitly banned same-sex marriage.

That's when Windsor petitioned the Supreme Court to hear her case on an expedited basis.

“I’m 83 years old,” Windsor said, adding that while she felt “great” about the hearing, she has a number of health problems.

Her spouse didn’t get to see the legality of their marriage resolved in her lifetime, Windsor said, but she hopes that she will.