Thomas John Umberg (born September 25, 1955, Cincinnati, Ohio) is a retired U.S. Army Colonel, former federal criminal prosecutor, small business owner, and Democratic politician currently serving as a member of the California State Senate representing the 34th District — covering Santa Ana, Anaheim, Fullerton, Buena Park, La Habra, Placentia, and the west side of Orange in northern Orange County. He is term-limited from the Senate in 2026 and is running for Member, California State Board of Equalization, 4th District in the June 2, 2026 primary. He is endorsed by Governor Gavin Newsom, U.S. Senators Adam Schiff and Alex Padilla, and Attorney General Rob Bonta — the most powerful statewide endorsement coalition in the BOE District 4 race.
Umberg was born in Cincinnati and grew up in California. He has a bachelor’s degree from UCLA and a law degree from UC Hastings. He began his military service at the Korean DMZ and was deployed overseas for three tours — totaling over five years — including assignments as a paratrooper with the Army Special Operations Command and the XVIII Airborne Corps. He served active military duty again in 2009, leading the U.S. military effort to attack corruption within the Afghan Army and Police, for which he was awarded a Bronze Star for meritorious service in a combat zone. He retired from the Army at the rank of Colonel. As a federal criminal prosecutor, Umberg had a 100% conviction rate, trying numerous white collar, civil rights, and gang cases and successfully trying over 100 cases to verdict or judgment. He is the founding partner of Umberg Zipser LLP, a veteran-owned Orange County boutique law firm recognized by Best Lawyers and The Daily Journal as one of California’s preeminent firms.
Umberg served three terms in the California State Assembly (1990–1994 and 2004–2006), representing central Orange County, authoring 76 laws and bringing more than $563 million in funds to Orange County. He served as Deputy Drug Czar for President Bill Clinton, responsible for foreign drug interdiction, counter-drug intelligence, and international drug policy. He was appointed Co-Chair of the U.S. State Department’s Public Private Partnership for Justice Reform in Afghanistan in 2011. He was elected to the State Senate in 2018, defeating incumbent Republican Janet Nguyen, and re-elected in 2022. In the Senate he has served as Chair of the Senate Judiciary Committee and the Senate Elections Committee. He is married to retired Brigadier General Robin Umberg. They have three children.
Endorsements
Governor Gavin Newsom, U.S. Senator Adam Schiff, U.S. Senator Alex Padilla, Attorney General Rob Bonta, California Professional Firefighters, and labor unions representing healthcare workers, educators, and nurses. Also endorsed by State Senator Scott Wiener and a coalition of LGBTQ leaders across California. A full list is available on his endorsements page.
Reputation/Scandals/Successes
Core Strengths and Positive Reputation
- Most Powerful Endorsement Coalition in the Race: Umberg is the only candidate in the BOE District 4 race endorsed by Governor Newsom, both U.S. Senators, and the State Attorney General — the full weight of California’s Democratic establishment. In a low-information, low-turnout primary for a down-ballot office most voters have never heard of, name recognition driven by high-profile endorser associations is among the most decisive factors in who advances. Newsom’s endorsement in particular is a meaningful signal of institutional trust and may come with bundled donor networks and organizing infrastructure.
- Deepest Sacramento and Federal Policy Experience in the Field: Umberg’s career spans federal prosecution, national drug policy, three Assembly terms, two Senate terms, Senate Judiciary Committee chairmanship, a State Department advisory role, and military leadership on anti-corruption efforts in Afghanistan. No other candidate in the BOE District 4 race has worked at the intersection of law enforcement, public accountability, and legislative oversight at this scale — all skills directly relevant to a board whose remaining authority centers on oversight, appeals, and accountability.
- Prosecutorial Background Directly Relevant to BOE Oversight Role: Umberg has spent his career holding powerful institutions accountable, protecting public funds from fraud and abuse, and enforcing the law without fear or favor. His 100% conviction rate as a federal prosecutor — including white-collar, civil rights, and gang cases — and his work attacking corruption in the Afghan military establish a record of institutional accountability that is directly applicable to the BOE’s oversight of county assessors and large corporate property valuations. He has argued the BOE needs more investigative power and resources to fulfill this function.
- Orange County Name Recognition and Voter Base: Umberg has won four elections in Orange County legislative seats — twice in the Assembly and twice in the Senate, including defeating incumbent Republican Janet Nguyen in 2018 — establishing him as the most electorally tested Democrat in Orange County among the BOE candidates. Since Orange County is the district’s largest county, his name recognition there is a structural advantage over the San Diego-based Democratic candidates.
- Small Business Credibility and Bipartisan Track Record: As the founding partner of a veteran-owned law firm with multiple employees, Umberg brings genuine small business experience to his platform. During his Assembly tenure, he worked across party lines, authoring 76 laws and bringing more than $563 million in funds to Orange County. His record of bipartisan legislating in a competitive Orange County district — and his multiple Legislator of the Year awards — reflect an ability to govern pragmatically that differentiates him from more ideologically defined candidates.
Criticisms and Vulnerabilities
- Multiple Prior Statewide Electoral Losses: Umberg ran unsuccessfully for California Attorney General, Insurance Commissioner, and Orange County supervisor before finding his way back to the legislature in 2018. His record of losing high-profile races is well-documented and will be used by opponents to raise questions about his electoral ceiling, particularly outside Orange County. While his Assembly and Senate wins are genuine accomplishments, the pattern of failed statewide bids is an unusual one for a candidate seeking a statewide office.
- The BOE as a Landing Spot for a Term-Limited Politician: Critics — including CalMatters and LAist, which have noted that the BOE has become a “launching pad” and “landing spot” for career politicians — have raised the implicit question of whether Umberg is running for the BOE out of conviction about property tax policy or because he is term-limited from the Senate and needs a next office. His opponents with more direct BOE or assessor-office experience (Petterson, Arias) have drawn this contrast explicitly, arguing the office requires technical tax expertise rather than legislative credentials.
- Progressive Courage Score Criticism: The Progressive Voters Guide notes that Umberg has not supported key bills on youth justice, affordable health care, support for homeless outreach workers, or public safety as measured by Courage California’s legislative scorecard. For progressive Democratic voters in San Diego and Riverside counties who may be choosing between Umberg and more progressive-aligned candidates like Arias or Petterson, this voting record could be a meaningful differentiator.
- Limited Technical Tax and Assessment Experience: Unlike Petterson (BOE chief deputy), Arias (county assessor taxpayer advocate), or Bilodeau (licensed engineer with infrastructure finance background), Umberg brings no direct property tax assessment, BOE operations, or utility valuation experience. His case for the BOE rests on accountability and oversight credentials — a strong argument for the office’s watchdog function, but one that opponents argue does not address the technical demands of overseeing $167 billion in corporate property assessments and hearing complex taxpayer appeals.
Campaign Contributors
Umberg entered the race with the most substantial fundraising infrastructure in the Democratic field, drawing on a donor network built across decades of Orange County legislative campaigns and backed by labor union support. Full contributor details are available at Transparency USA.
Media Coverage
CalMatters: Why Are So Many People Running for Board of Equalization in 2026?
KPBS: 2026 Primary Election — Board of Equalization District 4 Race Explainer
LAist: Lawmakers Stripped the Board of Equalization of Power. Now They’re Fighting to Join It.
