Mark Bryan

Deputy County Administrator

Mark Bryan has played a significant role in Yolo County for almost three decades. He started as a Forensic Clinician and has since earned multiple leadership positions during his tenure. Currently serving as Deputy County Administrator, Mr. Bryan works with leadership throughout the County. He collaborates closely with officials to guarantee that residents access high-quality, cost-efficient, and streamlined services across all programs. He holds a Master's Degree in Social Work from California State University, Sacramento, and is also a Credentialed County Senior Executive recognized by the California State Association of Counties (CSAC).

Natalie Dillion

Director of Child Support Services

Natalie had been the Director of the Yolo County Department of Child Support Services and previously worked as Deputy Director for the California Child Support Directors Association (CSDA). At CSDA she was heavily involved in the coordination of California local child support agency input in matters of automation, policy, and outreach. She was responsible for the Association’s participation in and development of educational material, training and conferences. Natalie received the CSAC (California State Association of Counties) credential for County Senior Executives and is the recipient of the 2008-2009 American Society of Public Administrators (ASPA) Award for Intergovernmental Cooperation, the CSDA CCSAS Excellence Award and in 2022 received the CSDA Truly B. Knox award.

Rachelle Gayton

Chief Probation Officer

Rachelle Gayton has over 20 years of public sector experience. She began her tenure with Yolo County in 2006 when she was hired as a Detention Officer at the Yolo County Juvenile Detention Facility. Since that time, she has worked her way up the ranks, becoming a Deputy Probation Officer in 2008 where she gained experience in each of the different probation divisions, in 2015 she was promoted to a Supervising Probation Officer, overseeing the Adult Services Unit until she was promoted to Probation Division Manager in 2018 where she has had the responsibility of overseeing operations for the Probation Division. 

Lee Gerney

Director of Innovation & Technology (IT)

Lee is the Director of the Innovation and Technology Services Department, where he oversees the delivery of IT services across Yolo County. Leading a dedicated team of 41 employees, he ensures the county's technology infrastructure is efficient, secure, and meets the needs of its users. Lee began his public sector career at Marysville School District in 1998. In 2004, he joined Yolo County's IT network team, was promoted to Chief Information Security Officer in 2007, and rose to the position of Chief Technology Officer in 2020. Demonstrating his commitment to county leadership, he earned the “Credentialed California County Technology Executive” certification through CSAC in 2019. Residing with his family at the base of the beautiful Sutter Buttes in Sutter County, Lee is guided by the principle: “A leader takes people where they want to go. A great leader takes people where they don’t necessarily want to go, but ought to be.”

Tom Haynes

Director of Financial Services

Tom Haynes was appointed as Chief Financial Officer in October 2023. Tom has been with Yolo County since 2015, beginning his tenure as the Chief Budget Official before promoting to Assistant Chief Financial Officer in 2019. Tom has over 20 years of experience in local government finance, and is committed to being a steward of public funds and ensuring the County’s long-term financial sustainability. Tom holds bachelor’s degrees in Political Science and Economics and a master’s degree in Economics from San Diego State University.

Humberto Izquierdo

Director of Agriculture

Diana Lopez

Library

Diana Lopez is originally from the Pasadena area of Southern California and moved to the Bay Area eleven years ago to take a position managing the Marin City Library, a branch of the Marin County Free Library. During her eight and a half-year tenure in Marin County, she led education equity initiatives, outreach, and managed the two school libraries in the Sausalito Marin City School District with support from an embedded team. Before moving to the Bay Area, she worked at Pasadena City College Library for eight years teaching information literacy and library services and coordinated outreach activities. The work that Diana and her team did in Marin City was highlighted by a GARE issue brief in 2018. Diana was named a Mover and Shaker, Advocate by Library Journal in 2019.

Tom Lopez

Undersheriff

Sheriff Tom Lopez was born and raised in Yolo County. Tom is a fifth generation Yolo County resident. He attended school in the Esparto School District and joined the Sheriff’s Office in 1980 as a Reserve Deputy Sheriff upon graduating from High School. He returned to the Yolo County Sheriff’s Office in 1988 as a Resident Deputy and Field Training Officer in the Esparto–Capay Valley area. He was promoted to Undersheriff-Coroner in January 2007 where he was responsible for the day-to-day operations of the Sheriff’s Office.  He held this position for 12 years prior to being elected Sheriff ~ Coroner ~ Public Administrator on June 5, 2018.  His term began on January 7th, 2019.  Sheriff Lopez was re-elected in 2022 and in January of 2023 he began serving a six-year term. Tom holds a bachelor’s degree in criminal justice and was also active in his community serving as a volunteer fireman for the Esparto and Madison Fire Districts.  Tom was the Fire Chief of the Madison Fire Protection District for 10 years before retiring after 34 years of service.

Mónica Morales 

Director of Health and Human Services Agency

With more than two decades of experience, Morales served as director of the Health Services Agency for the County of Santa Cruz and started with Yolo County in June 2025. She holds a Master of Public Administration in public policy and administration from Columbia University and a Bachelor of Arts in sociology from the University of California, Santa Cruz. Morales also serves as a commissioner with the Central California Alliance for Health and participates in several statewide public health and policy committees. Stepping into the role during a time of significant policy transformation, Morales will focus on ensuring Yolo County remains responsive and resilient by preserving essential services, meeting mandated responsibilities, and navigating evolving federal and state frameworks with community in mind.

Tracie Olson

Public Defender

Tracie Olson joined the Yolo County Public Defender’s Office in 1998. She has represented clients accused of crimes ranging from misdemeanors to capital murder. In 2009, Olson was appointed Chief Public Defender of Yolo County, the first woman in the history of the county to hold the position. Olson leads over 50 attorneys, investigators, and other advocates dedicated to providing individuals the highest quality legal representation through a model of interdisciplinary representation. Tracie Olson received her undergraduate Bachelor of Science degree from the University of California, Davis in 1992. She received her legal education at the University of Minnesota Law School where she graduated in 1997 Order of the Coif, an American honor society for law school graduates. Since 2018, Olson is a Board Member of the California Public Defenders Association. She helped found Yolo Public Defender CARES, a non-profit corporation organized to assist justice involved individuals. Olson is a CSAC Credentialed California County Senior Executive and a graduate of the National Association of Counties’ High Performance Leadership Academy.

Ryan Pistochini

Director of General Services

Philip Pogledich

County Counsel

Phil Pogledich joined Yolo County in 2004 as a Deputy County Counsel and was appointed County Counsel in 2014. Prior to joining the County, Phil was an associate attorney in the San Francisco and Sacramento offices of Pillsbury Winthrop Shaw Pittman LLP. He is a lifelong resident of Northern California and attended college at UC Davis followed by law school at the University of California College of the Law, San Francisco (formerly UC Hastings). Phil and his family reside in Davis.

Jeff Reisig

District Attorney

Jeff Reisig has been a prosecutor since 1997 and has been the county’s chief elected law enforcement official since 2007. During his tenure as DA, Reisig has focused intently on advocating for victims of crime and pursuing a balanced approach to public safety through methods designed to enhance accountability while also embracing programs to reduce recidivism and the criminal justice footprint. Reisig has also developed multiple highly successful diversion programs to help those suffering from serious addiction and mental illness. Reisig was the first prosecutor in the nation to launch a third-party hosted data-transparency portal which provides the public nearly unrestricted access to criminal justice data from his office, while also giving community members a platform to directly share their findings and engage policy makers and the media on the data.

Jesse Salinas

Assessor/Clerk Recorder/Elections

Jesse Salinas has a combined 34 years of experience in the public and nonprofit sectors, 25 years of which have been in the public sector at both the state and local level. Jesse currently serves as Yolo County’s Assessor/Clerk-Recorder/Elections official. Known as Yolo’s ACE, Jesse is spearheading a joint public/private leadership academy with the University of California at Davis Graduate School of Management and serves in various Board leadership capacities at the state and local level.

Mike Webb 

Chief Administrative Officer

Mike Webb brings nearly three decades of public service experience to the role. Previously serving as City Manager for the City of Davis since 2017, Webb has held leadership positions in economic development, land use planning, resource conservation, and policy development. His career is marked by strategic fiscal stewardship, intergovernmental collaboration, and a commitment to ethical governance. A UC Davis alumnus with a Master of Public Administration from USC, Webb has played a key role in major initiatives such as Healthy Yolo Together, affordable housing projects, and sustainability efforts recognized at the state level. As County Administrator, he is dedicated to advancing the Board of Supervisors’ vision, fostering community engagement, and ensuring Yolo County’s continued progress and resilience.