Gregory J. Sebastinelli

Deputy County Counsel

Gregory J. Sebastinelli joined the Office of the County Counsel in 2001.  He currently serves as an attorney in the Probate section and represents the Office of the Public Guardian in litigation.  His primary practice areas include probate, probate litigation, financial elder abuse, conservatorships, and conservatorship and trust administration.

From 2001 to 2013, Greg served as an attorney in the Litigation section where he handled complex defense cases. During that time, he successfully tried seven cases.  He defended the County in a multi-million dollar business dispute involving the County Fairgrounds and obtained a dismissal.  He also obtained a defense verdict in a dispute involving a real property sale at public auction in which over $1,300,000 was sought in damages.  And in 2010, Greg defended the County in a medical malpractice case in which the patient alleged a failure to properly diagnose a cerebral aneurysm and sought $2.5 million in damages.  After just one hour of deliberation, the jury returned a defense verdict.

Greg has presented training and risk management seminars involving general government, employment (labor relations and collective bargaining), custodial care, and medical issues.

Greg’s professional expertise includes:

  • Civil litigation, including medical malpractice and employment litigation
  • Probate and mental health conservatorships
  • Conservatorship and trust administration
  • Probate and elder abuse litigation
  • Decedent estate administration


  • University of San Francisco School of Law, J.D., 1982
  • University of San Francisco, B.S. (Business Administration), 1979
  • Loyola University of Chicago, Rome Center, 1977
  • Saint Ignatius College Preparatory, 1975

Professional Associations

  • Santa Clara County Bar Association
  • Court-appointed arbitrator in Santa Clara and San Mateo Superior Courts

Prior Experience

  • Equity partner with Clapp, Moroney, Bellagamba & Vucinich where he successfully tried over 15 cases, including more than 10 jury trials

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