Since retiring from the Superior Court in 2005, Judge O’Brien has served as a neutral mediator in more than 600 cases, and has presided over 50 arbitrations and private trials and 20 discovery references.
Judge O’Brien’s numerous articles have been published in (alphabetically) the CEB Civil Litigation Reporter, Gavel to Gavel, Journal of the California Dental Association, Judicature, the Loyola Law Review, the Metropolitan News-Enterprise, National Review, The Bench, The Glendoran, the Los Angeles Daily Journal, the San Gabriel Valley Tribune and the San Pedro News-Pilot. He is also a current member of the Board of Editors of The Bench.
Judge O’Brien has been a guest law school lecturer at Loyola Law School, Pepperdine University Law School and Whittier Law School. He has also served as a lecturer, moderator and/or panelist at continuing education programs of the California Judges Association, the California Center for Judicial Education and Research, the Los Angeles Superior Court, the Trial Practice Inn of Court of the Los Angeles County Bar Association, the East Valley Bar Association, the law firm of Snell and Wilmer, the Southern California Mediation Association and the USC Law School Alumni Association.
Judge O’Brien is a member and chair of the Civic Center Advisory Committee of the City of Rancho Palos Verdes. The committee is tasked with advising the City Council on the development of a new City Hall complex. He has previously served as a member and vice chair of the City’s Finance Advisory Committee and as a member of the RDA Dissolution Oversight Board. He has also served an appointed three-year term on the ADR Committee of the California State Bar Association, and served for five years on the ADR Committee of the California Judges Association (CJA). He was CJA president 2002-03 and continues to serve the organization on various committees and as a conference speaker and panelist.
Judge O’Brien is a member and past president of the Rotary Club of Palos Verdes Peninsula and a past president of the Rotary Club of West Covina. In 2016-17 Judge O’Brien served as District Governor of Rotary District 5280 (Greater Los Angeles). He is also a member of the Paul Harris Society and is a Major Donor to The Rotary Foundation.