Hon. Sheila Prell Sonenshine (Ret.) Featured in California Supreme Court Historical Society book California Legal History

JAMS is proud to recognize Hon. Sheila Prell Sonenshine (Ret.), who was recently featured in California Legal History, published by the California Supreme Court Historical Society. The book highlights the trailblazing careers of women in California’s judiciary, including Justice Sonenshine’s historic appointment as California’s first female Jewish American justice and the youngest appellate justice in the state’s history.

Her groundbreaking work, including the establishment of California’s first mandatory appellate settlement conference program, helped shape the evolution of alternative dispute resolution (ADR). Today, she continues to bring her vast experience, pragmatic problem-solving skills and unwavering commitment to justice to her work as a JAMS mediator, arbitrator and special master/referee.

A Trailblazing Career in the Law

Justice Sonenshine’s career has been defined by leadership, innovation and a commitment to excellence. After earning her law degree from Loyola Law School, she quickly established herself in the legal profession by founding and managing a successful law firm in Newport Beach. She handled a diverse range of cases, developing a reputation for her sharp legal acumen and ability to resolve complex disputes efficiently.

Her judicial career began in 1981 with an appointment to the Orange County Superior Court, where she served as presiding judge of the Family Law Panel. The following year, she was elevated to the California Court of Appeal, Fourth Appellate District, Division Three, where she heard thousands of cases over 16 years, authoring numerous published opinions that continue to shape California law.

Among her many contributions, Justice Sonenshine was a pioneer in appellate ADR. Recognizing the inefficiencies of prolonged litigation, she established the state's first mandatory appellate settlement program, which achieved an impressive 44% settlement rate. This forward-thinking initiative helped set a precedent for integrating mediation and settlement into the appellate process—a philosophy that remains central to modern ADR.

Commitment to Justice, Gender Equality and ADR

Beyond her judicial service, Justice Sonenshine has been a passionate advocate for advancing fairness and efficiency in the legal system. She was a key member of California’s first statewide judicial commission on gender bias, which examined disparities in judicial decision-making.

She also established the Sonenshine Pro Bono Reception, an annual event that has, for 30 years, connected attorneys with pro bono opportunities to support underserved communities.

Reflecting on the legal profession’s progress, she recently shared:

"In the past 50-plus years since I became a lawyer, our judiciary, mediators and arbitrators have made significant progress on hearing matters based on facts and law, not their personal conscious or subconscious prejudices or assumptions. I am heartened to see the strides made by our judiciary regarding race, gender, age and religious diversity. But being completely candid, I think we have a long way to go and are nowhere near where we need to be in terms of equality and inclusiveness."

A Lasting Impact in ADR

Since joining JAMS, Justice Sonenshine has continued to demonstrate the practical wisdom and fairness that defined her judicial career. She is known for her ability to resolve complex, high-stakes disputes across a range of practice areas, including business and commercial, family law, employment, real estate, probate and trusts, and professional malpractice.

Her decades of mediation experience and her settlement-focused approach make her an invaluable resource to attorneys and litigants in crafting equitable and fair solutions. Whether she is deciding complex business disputes or sensitive family law matters, Justice Sonenshine’s background in trial and appellate courts has earned her a reputation as a trusted and highly regarded judge.

Conclusion

Justice Sonenshine’s chapter in California Legal History is a testament to her enduring influence on the legal and ADR communities. Her trailblazing career, commitment to justice and innovative approach to dispute resolution continue to inspire lawyers, judges and neutrals alike.

To read the full chapter on Justice Sonenshine’s career and explore more about the history of women in California’s judiciary, download California Legal History, Vol. 19, by Hon. Shama Hakim Mesiwala, from the California Supreme Court Historical Society here.