William J. O’Brien, 77, a prominent Philadelphia trial lawyer, died May 7 at his home in Chestnut Hill after a long illness.

Mr. O’Brien was a founding member of Conrad O’Brien and chairman emeritus of the firm where he had practiced for more than 30 years.

He began his legal career at what is now Pepper Hamilton, where he became a partner before leaving to start the Conrad O’Brien firm. As a lawyer he represented a wide range of clients that included Fortune 500 companies, law firms, hospitals and individuals.

Among his most notable cases was his defense of John DuPont, the chemical fortune heir, in a civil lawsuit for wrongful death brought by the wife of David Schultz, an Olympic wrestler who had been shot by DuPont. In his last jury trial, he obtained a defense verdict on behalf of a major law firm in a legal malpractice action claiming over $20 million in damages.

Jim Rohn, chairman of Conrad O’Brien who had worked with Mr. O’Brien for more than 23 years, said Mr. O’Brien’s trial skills were “legendary.”

“It was his ability to connect with people that made him so effective and unique,” Rohn said.

He was a Fellow of the American College of Trial Lawyers and of the International Academy of Trial Lawyers. He was a past President of the Philadelphia Association of Defense Counsel and a recipient of its Distinguished Service Award.

He lectured extensively on trial advocacy, including serving as an adjunct professor of trial advocacy at Temple University’s School of Law.

He was a graduate of LaSalle University and Villanova University’s School of Law.

Mr. O’Brien is survived by his wife, Lillian; a daughter, Nancy O’Brien Weidner; a son, William, Jr.; brothers James and Joseph; sisters Mary DiCondina, Susan Zimmerman, Kathleen Ferguson, Mildred O’Brien, and Fran O’Brien, and two grandchildren.


Memorial donations may be made to Villanova University School of Law, Class of ’62, or to Temple University James E. Beasley School of Law, Trial Advocacy.

Funeral services for Mr. O’Brien were held May 10 at Our Mother of Consolation Church in Chestnut Hill.