David M. Rosenblum, 47, of Collingswood, a civil rights lawyer who had been legal director since 2011 for the Mazzoni Center in Philadelphia, died of a heart attack Friday, May 2, at Thomas Jefferson University Hospital.

The Mazzoni Center defines itself as the health-care and wellness center for the lesbian, gay, bisexual, and transgender community.

William P. Fedullo, chancellor of the Philadelphia Bar Association, praised Mr. Rosenblum and his work.

"David was a passionate advocate for the legal rights of the LGBT community and a beacon of our public interest community," Fedullo said in a statement.

"He was instrumental in the creation of the Philadelphia Bar Association's Committee on the Legal Rights of Lesbians and Gay Men in 1997 (now the LGBT Rights Committee)."

The committee, he noted, monitors "relevant conditions and trends in the law, and the treatment of LGBT individuals in the legal profession.

"He was a warm and charismatic person with an enduring devotion to civil rights work and a willingness to help all. He will be greatly missed."

Mr. Rosenblum was chair of the Gay and Lesbian Lawyers of Philadelphia from 1995 to 1998 and a board member of the group from 1994 to 2002, Shannon Duffy, a longtime friend, said.

A member of the National LGBT Bar Association, Mr. Rosenblum was the chair of its 2002 annual conference, Lavender Law, in Philadelphia, Duffy said.

At Villanova University School of Law, from which he graduated in 1991, Mr. Rosenblum was a founding member of the Public Interest Law Society. In that year, the Villanova Law Review published his student paper, "Custody Rights of Gay and Lesbian Parents."

In 2013, the Drexel University School of Law gave him its Diversity Award.

Mr. Rosenblum began his career as a trial lawyer in the Philadelphia office of the U.S. Equal Employment Opportunity Commission in 1991, Duffy said.

He worked as a New Jersey deputy attorney general with that office's employment counseling unit from 2000 to 2008, and was an equal employment opportunity officer with the New Jersey Department of Labor from 2008 to 2011.

Since 2011, he had been an adjunct professor at the law school of Temple University, teaching a course on sexual orientation, gender identity, and the law.

Mr. Rosenblum graduated from Upper Merion High School in 1984, where he performed in the marching band and in stage productions, Duffy said.

At Brandeis University, where he earned a bachelor's in philosophy in 1988, he was musical director for two student productions.

At Villanova Law, he was musical director and chair of the Villanova Court Jesters, which at the time staged annual Gilbert and Sullivan operettas.

From 1999 to 2007, he was a performer in eight shows of the Savoy Company in Philadelphia and from 2002 to 2005 was a member of its board of directors.

Mr. Rosenblum is survived by his husband, Stephan Stoeckl, whom he married in 2013, parents Ruth and Howard Rosenblum, a brother, and a sister.

Information about a pending memorial service is to be posted at www.mazzonicenter.org.

Donations may be sent to www.mazzonicenter.org/contribute/donate.

Condolences may be offered to the family at www.fosterwarnefuneralhome.com.