He has been a state prosecutor since 2002. Chamberlain is the legal counsel to California’s Bureau of Forensic Services, providing advisory and training services to laboratory management and staff involving all forensic disciplines. He represents California in federal and state involving constitutional and admissibility challenges to DNA and other forensic evidence, in addition to general felony appellate caseload. Chamberlain provides legislative advice, including participation in drafting and leading implementation of California’s DNA Database Act and Familial DNA Search Program.