Cassandra Quin Butts, a Deputy White House Council, policy expert and a law school classmate of President Barrack Obama, died May 26 of cancer. She was 50.

Butts was selected shortly after the 2008 presidential election to serve as Deputy White House Council, focusing primarily on domestic policy and ethics. She was also on the advisory board for the 2008 presidential transition team. Butts stepped down as deputy council in November 2009 to serve as senior advisor in the office of the Chief Executive Officer at the Millennium Challenge Corporation, a bilateral U.S. foreign aid agency charged with implementing a new philosophy toward foreign aid.

In February 2014, President Obama nominated Butts to be the ambassador to the Bahamas but by February 2015 the Senate had not confirmed her to the post. At the time of her death, her nomination remained pending before the Senate on its executive calendar.

Butts’ tenure as Deputy White House Council saw her focus mainly on judicial nominations; days after Associate Justice David Souter announced his retirement from the U.S. Supreme Court, Butts was in frequent contact with President Obama’s eventual nominee to replace Souter, Sonia Sotomayor. Early in the administration, Butts was rumored to be a candidate to lead the Equal Employment Opportunity Commission, as well as being a possible candidate for Secretary of Housing and Urban Development.

At her funeral on June 7, President Obama choked up and wiped away tears while delivering her eulogy, calling her his “moral compass” and describing her as “a person I trusted to make sure that everyone I hired understood the values of this administration. She made me better, and I believe she made us better.”

Butts was found dead in her Washington, D.C. home by her sister. The family said she had suffered from a brief illness likely brought on by her battle with leukemia. Relatives told the press that Butts had not been ill until days before her death.

The Brooklyn, N.Y. native attended the University of North Carolina at Chapel Hill and in 1991 graduated from Harvard Law School where she and President Obama became close friends. She worked as a YMCA counselor during her undergraduate years, then served as a researcher with the African News Service in Durham, N.C. Butts did litigation and policy work for the NAACP Legal Defense and Educational Fund and spent seven years working as a senior advisor to former Missouri Rep. Dick Gephardt. Later she would become senior vice president for domestic policy at the Center for American Progress.