David W. O'Brien, a member of the California and New Hampshire bars, received his Bachelor of Education from Plymouth State University in 1950 and the degree of Doctor of Law from the University of San Francisco in 1960. He is admitted to the U.S. District Courts, Districts of New Hampshire and California. He is also a member of the American Bar Association.
   Retired Workers' Compensation Administrative Law Judge (WCALJ) O'Brien served as a Workers' Compensation Judge with the California Workers' Compensation Appeals Board, as an Administrative Law Judge with the California Unemployment Insurance Appeals Board, as a Deputy Commissioner of Corporations for the State of California, and as a Senior Counsel for the State Compensation Insurance Fund. He has also devoted many years to the private practice of law as both a defense and plaintiff attorney, serves as an expert witness in civil cases and is a Certified Administrator for Self-Insurance Plans.
   During the Korean War, Judge O'Brien served as a special agent in the Counter Intelligence Corps.

   David Zimmerman was a Judge at the Workers’ Compensation Appeals Board (WCAB) for 19 years.  He retired from the bench in July of 2004.  Prior to being appointed as a Judge, Mr. Zimmerman was the attorney in charge of the State Compensation Insurance Fund (SCIF) office in Los Angeles and later in Long Beach.  While he was an attorney in charge, Mr. Zimmerman tried all of the cases involving politicians in Los Angeles County including Los Angeles County Assessor, Philip Watson, Los Angeles County District Attorney, Joseph Busch, and Los Angeles County Supervisors, Warren Dorn and Ernest Debs.
   Mr. Zimmerman was an attorney in the State of Michigan prior to moving to California where he was engaged in the general practice of law.
   Mr. Zimmerman has been certified as an Arbitrator by the Administrative Director’s office of the Division of Workers’ Compensation.