Dr. David Duncan is a board-certified family medicine and addiction medicine physician with over two decades of clinical and leadership experience in correctional, military, and federal health systems. He currently serves as a telemedicine consultant with the Addiction Medicine Central Team for the California Department of Corrections and Rehabilitation (CDCR), providing expert care for substance use disorders across all 31 CDCR institutions. He also mentors primary care providers and addiction medicine fellows from UCSF and UCLA.

Dr. Duncan earned his Doctor of Osteopathic Medicine from Touro University College of Osteopathic Medicine in 2001, following his Bachelor of Science in Biology (summa cum laude) from Pacific Lutheran University in 1995. He completed his internship at Naval Hospital Camp Pendleton (2001–2002), Flight Surgeon training at the Naval Aerospace Medicine Institute (2003), and family medicine residency at Naval Hospital Bremerton (2005–2007).

He served in several key roles during his active-duty tenure. From 2003 to 2005, he was Airwing Flight Surgeon for the Navy’s forward-deployed Carrier Air Wing 5 during Operation Iraqi Freedom. He later served as Staff Family Physician at Branch Health Clinic Iwakuni, Japan (2007–2010), and then as Senior Medical Executive for the U.S. Coast Guard Alameda Clinic (2010–2014), overseeing care for over 3,000 active-duty personnel and supervising senior medical staff.

From 2014 to 2022, Dr. Duncan served as Clinical Director at the Federal Correctional Institution in Dublin, CA, where he led clinical operations, supervised a multidisciplinary team, and managed care for over 1,300 incarcerated women. He played a pivotal role in national policy implementation on transgender care and opioid use disorder treatment, and was named Clinical Physician of the Year in 2020 by the U.S. Public Health Service.

Board certified by the American Board of Family Medicine and the American Osteopathic Academy of Addiction Medicine, Dr. Duncan holds numerous certifications and has remained actively involved in teaching, policy development, public health deployments, and national recruitment efforts throughout his career.