Roberta Kaplan, partner at Paul Weiss Rifkind Wharton & Garrison
Roberta Kaplan, partner at Paul Weiss Rifkind Wharton & Garrison (Photo by Diego M. Radzinschi/THE NATIONAL LAW JOURNAL.)

It is no small feat for lawyers or a law firm to topple a federal law that writes “inequality into the entire United States Code,” in the words of Justice Anthony Kennedy. But that is exactly what Roberta Kaplan and Paul, Weiss, Rifkind, Wharton & Garrison achieved with the U.S. Supreme Court’s landmark decision last June in United States v. Windsor.

Kaplan, a firm partner, represented Edith Windsor in her challenge to the provision in the Defense of Marriage Act defining marriage as the union between a man and a woman. Windsor was legally married to Thea Spyer. When Spyer died in 2009, leaving her estate to Windsor, the widow was smacked with federal estate taxes of nearly $400,000 — taxes she would not have had to pay had she married a man.

“In her own words, she was indignant and wanted to do something about it,” Kaplan said of Windsor. Kaplan accepted the case immediately after meeting Windsor. “Those kinds of pro bono cases are so embedded in the firm, it didn’t even occur to me to ask the firm first.”

Firm chairman Brad Karp explained, “This is an extraordinarily important cause. Windsor is the embodiment of what we have been doing for many, many decades. It’s in our DNA.”

At its peak, the firm had about 40 lawyers from its tax and trusts and estates departments and the D.C. office working on the case, with Kaplan at the helm. Having a private law firm as support was a “huge advantage,” Kaplan said.

However, she was quick to credit outside support from the American Civil Liberties Union, the New York Civil Liberties Union and Stanford Law School’s Supreme Court clinic. And, she added, the most surprising support came when the Obama administration decided it would no longer defend the law.

Defending DOMA on behalf of the Bipartisan Legal Advisory Group of the House of Representatives was Paul Clement, a partner at Bancroft. Clement, who has argued more than 70 cases before the Supreme Court, did not respond to requests for comment.

The Windsor decision affects an array of rights and benefits in more than 1,000 federal laws and, although limited to legally married gay couples, its language is being used by gay rights groups to press their marriage cause around the country.

“I love what I do and have a great career, but there’s been nothing like this,” said Kaplan. “If you had told me in 2006 when we lost the New York marriage case that anything like this would happen, I would have said you were smoking crack.”