Kaplan, 46, will ask the justices to overturn the Defense of Marriage Act, a Clinton-era law that says the federal government doesn't recognize same-sex marriage.
As a corporate lawyer, Kaplan works mostly on complex business cases for clients including AIG, JPMorgan Chase, and Fitch Ratings. But she has told Business Insider that the "value of pro bono work is interwoven into the DNA" of Paul Weiss, and it's clear that she feels strongly about the DOMA case.
She represents Edith Windsor, an 83-year-old lesbian who had to pay $363,000 in estate taxes when her wife died that a straight spouse wouldn't have had to pay.
Kaplan, who's gay, has previously argued a case seeking to legalize gay marriage in New York. (She lost that case, but the Empire State eventually legalized same-sex marriage.)
When a friend introduced her to Windsor, she didn't hesitate before taking on her case. Kaplan was overjoyed and even had tears in her eyes when she found out Obama wasn't going to defend DOMA, according to an article on the case in "The Advocate."
Kaplan, who has been arguing this case since 2010, isn't afraid of high stakes.
"I'm a bit of a pressure junkie," she told Law Dragon back in 2006. "It's clearly part of my job. I clearly like the things that I do, and when things start to fall off, part of me feels like, 'What's wrong?' I'm not working hard enough or I'm not tense enough.'"
I've interviewed Kaplan several times on the phone, and despite her "pressure junkie" characterization, her most obvious quality is that she's really, really nice. She also seems sincerely to care about Windsor.
The legal brief Kaplan wrote for Windsor focused largely on the discrimination the 83-year-old had endured. While she worked on the case, Kaplan told me she kept a post-it note reading, "It's all about Edie, Stupid."
When talking to Law Dragon, Kaplan commented that the best litigators get along with people and are persuasive and have charisma.
That same characterization can apply to Kaplan, who already managed to persuade the Second Circuit Court of Appeals to overturn DOMA.
While Kaplan tends to focus on Windsor and not herself, the 46-year-old lawyer will almost certainly become a new hero to the gay rights movement if she can convince the Supreme Court to kill DOMA for good.
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