Alameda County's ALPR program
What public records and California law tell us about the Alameda County Sheriff's Office automated license plate reader program.
What is an ALPR? What is Flock?
California law defines an automated license plate recognition system as a searchable computerized database resulting from the operation of one or more mobile or fixed cameras combined with computer algorithms to read and convert license plates and related information into computer-readable data.
Flock Safety markets fixed license plate reader cameras and software to law-enforcement agencies for vehicle searches and alerts.
Source: California Civil Code § 1798.90.5 →
Source: Flock Safety — License Plate Readers →
The photograph isn't the issue. The searchable history is.
A plate visible on a public street is not secret. What changes with an ALPR network is the ability to convert repeated observations into records that can later be searched electronically.
That distinction is built into California's statutory definition itself: the law describes an ALPR system in terms of a searchable computerized database.
California limits ALPR data sharing
California Civil Code § 1798.90.55 restricts a public agency from selling, sharing or transferring ALPR information except to another public agency and only as otherwise permitted by law.
California Department of Justice guidance states that the statutory definition of public agency is limited to California state and local agencies and does not include federal or out-of-state law-enforcement agencies.
Source: California Civil Code § 1798.90.55 →
Source: California DOJ — 2023 ALPR guidance →
ACSO turned off Flock's National Lookup Tool for its data
The Alameda County Sheriff's Office told the Board of Supervisors that, after concerns arose in early 2025, ACSO asked Flock Safety to deactivate the National Lookup Tool for ACSO data. According to the Sheriff's Office, the change was completed in March 2025.
That is why questions about technical access controls, sharing settings, audit logs and oversight are not merely theoretical.
The verified contract ceiling reached $854,200
County records show a second amendment increasing the Flock agreement from $550,600 to $854,200, an increase of $303,600, and extending the stated contract period through 30 June 2026.
The Board approved that amendment 3–2 on 21 April 2026.
Source: Sheriff's contract submission →
Source: Board Summary Action Minutes, Item 55 →
ACSO reported 623 ALPR alerts in 2025
For 1 January through 1 December 2025, ACSO reported 623 ALPR alerts, including 60 alerts resulting in an arrest, 53 resulting in recovery of stolen vehicles, and 22 resulting in recovery of felony vehicles.
Those outcomes belong in the discussion. So does the denominator. The Sheriff's cited response does not provide the corresponding total number of vehicle observations collected to produce those results.
What we are not claiming
We have not yet verified a current Alameda County Sheriff's ALPR camera count or a later Flock contract superseding the agreement whose stated term ran through 30 June 2026. We will add those figures when credible records support them.
We also do not infer that the existence of a surveillance capability means Alameda County has deployed or used it.