Dan Cassidy, pre-eminent public sector labor relations attorney and founding member of Liebert Cassidy Whitmore passed away on December 19, 2025. He was 88 years old.
Dan Cassidy was among the most experienced and accomplished practitioners in the fields of public sector labor relations and employment law. Over the course of his career, Dan effectively advocated on behalf of counties, cities, special districts, community colleges and school districts in negotiations, arbitrations and civil service commission and other administrative hearings. Dan negotiated hundreds of labor agreements for public agency clients, including various public safety, general, professional, and supervisory units. He also represented public agencies as a presenter and panel member in numerous interest arbitrations and fact-finding proceedings.
During his career, Dan became a well-established and widely respected authority on labor relations. He lectured and trained on labor relations – at the National College of District Attorneys at the University of Houston School of Law, University of Southern California School of Public Administration, California State University at Long Beach and before numerous other professional and educational organizations.
Dan was born in Braddock, Pennsylvania but grew up in Burbank, California. Dan earned his bachelor’s degree from the University of Southern California (USC) and his Juris Doctorate from Loyola Law School, Los Angeles.
Dan began his legal career at Los Angeles County, eventually serving as Chief of the Labor Relations Division of the Los Angeles County Counsel’s office. He left the County to join Patterson & Taggert, where he met John Liebert. Together the pair, along with 4 other attorneys, formed our firm in 1980 and grew the firm’s practice to become California’s leading public sector, education and nonprofit management law firm which now has more than 120 attorneys in five offices.
Dan was a USC Trojan through and through. He was a longtime university volunteer for the USC Alumni Association Board of Governors, the USC Price Athenian Society Leadership Council, the USC Athletic Department Board of Counselors and the Spirit of Troy Marching Band Board of Directors. He served on the Half Century Trojans Board of Directors (including as President) and was honored with the Alumni Service Award in 2017.
Dan also remained active in the firm, providing mentoring to our attorneys as well as serving as a faculty member of our Leadership Academy.
Dan is survived by his beloved wife Terri, sons Tim (Chris), Stephen (Janelle) and Danny (Denise); daughters Kathy (Mike) and Jeanine (Joe), along with 14 grandchildren and 14 great grandchildren (with number 15 on the way).
He is also survived by hundreds of colleagues, friends and mentees whose lives have been changed due to his vision, leadership and presence. Regardless of school affiliation, in his memory we collectively strive to honor his legacy and FIGHT ON.
The family requests that any remembrances be made to the USC Half Century Trojan Scholarship Fund through this link:
https://giveto.usc.edu/?fundid=9818014414,9818014414,9818014414&appealcode=undefined&buttongen=1
(Questions regarding donations can be directed to the USC University Advancement office 213-740-7500 or uscadvancei@usc.edu).