Alameda County Sheriff | License plate readers
More than a hundred Flock cameras across the unincorporated county since 2023. The county's own procurement papers describe them; the office's policy for them is not something we have read.
At a glance
- Cameras
- More than 100, installed in the unincorporated areas of Alameda County [1]
- Vendor
- Flock Safety, contracted in 2023 [1]
- What the county says they are for
- To determine whether a vehicle was at the scene of a crime or involved in the commission of a crime [1]
- Exact camera count
- the county document says "over 100" and gives no precise figure [1]
- Retention
- not stated in any document we read. The office's plate reader policy is not in our corpus [1]
- Cost
- not stated in the document that describes the system [1]
- Who the data is shared with
- not stated in any document we read. The San Francisco Police Department's 2024 annual report lists "Alameda County CA SO" among roughly 230 California agencies it shared plate data with, which shows a sharing relationship in that direction and says nothing about this office's own sharing [2]
- Connection to the drone programme
- The county says the plate reader system is the reason only one vendor could supply its proposed drone-as-first-responder system [1]
How it happened
- Procurement
The office contracts with Flock Safety
A later county procurement document records that "In 2023, the Sheriff's Office contracted with Flock Safety for the Automated License Plate Recognition (ALPR) system, and over 100 ALPR cameras were installed in the unincorporated areas of Alameda County." [1]
- Context
San Francisco lists this office among its data recipients
The San Francisco Police Department's annual surveillance report for 2024 names "Alameda County CA SO" in its list of roughly 230 California law enforcement agencies that received San Francisco plate reader data. That is one direction of one relationship, recorded by the sending agency. [2]
- Procurement
The plate readers become the reason for a sole-source drone purchase
Asking the Board to approve a Flock Safety drone system without competition, the office writes that the product "is the only product that can seamlessly integrate with ACSO's existing Flock Safety ALPR system and Flock operating software." [1]
What one procurement document tells us
The Sheriff’s Office runs license plate readers across the unincorporated parts of Alameda County. We know that from a single sentence in a county purchasing item written for a different purpose:
In 2023, the Sheriff’s Office contracted with Flock Safety for the Automated License Plate Recognition (ALPR) system, and over 100 ALPR cameras were installed in the unincorporated areas of Alameda County. The ALPR cameras are used to determine whether a vehicle was at the scene of a crime or involved in the commission of a crime.
That is the county’s own account of what the cameras are and what they are for. It is also very nearly everything we can tell you.
What we could not find, and where we looked
California law requires an agency that operates plate readers to publish a usage policy: what it collects, how long it keeps it, who may look at it, and who else may receive it. For most agencies on this site, that policy is the backbone of the page.
We have not read one for this office. The five Board of Supervisors packets we retrieved contain no mention of plate readers, license plates or the vendor anywhere except the procurement item quoted above. We checked that our search was working by running it against a term we knew was there.
That is a statement about our own reading, not about the office. The office maintains a transparency portal we have not swept, and a policy may well be sitting on it. Until someone reads it, this page carries a camera count and a purpose and no rules.
The cameras that decided the drones
The reason this system matters beyond its own footprint is what came next.
In July 2025 the office asked the Board to approve a drone system from the same vendor, without competitive bidding, and gave this reason: the product “is the only product that can seamlessly integrate with ACSO’s existing Flock Safety ALPR system and Flock operating software.”
A choice made about cameras in 2023 became the stated reason there was only one possible supplier for aircraft in 2025. The county presents that as an operational advantage, and it is one. It is also the clearest example this site has found of a platform decision reaching forward in time.
One thread from across the bay
San Francisco’s police department publishes an annual report listing every outside agency it shared plate data with. In the 2024 report, “Alameda County CA SO” appears on that list, among roughly 230 California agencies.
That tells you one direction of one relationship, recorded by the agency doing the sending. It does not tell you what this office received, what it did with it, or what it sends anywhere else. We include it because it is a documented link between two counties on this site, and because it is the only external record of this system we have.
What we do not know
- What the office's plate reader policy says. California law requires an agency operating plate readers to publish a usage policy. We have not read one for this office. The five Board of Supervisors packets in our corpus contain no mention of plate readers apart from the single procurement document this page rests on, and the office's transparency portal has not been swept, so this is a gap in our reading rather than a finding about the office.
- How long this office keeps plate data, who may search it, and what is required before a search.
- The exact number of cameras, where they are, and what the system costs. The county document says "over 100" and gives no figure, no locations and no price.
- Which agencies this office shares its plate data with, and on what terms.
- Whether the cameras have grown in number since 2023. The only count we have is from a document describing a 2023 contract.
What you can do
Show up
Systems like this one are approved by boards, councils and committees that meet in public. We have not yet confirmed where each of them meets in Alameda County.
What we have documented in Alameda County →Protect yourself
Practical steps to shrink your personal data trail. Our guides publish at launch; until then, EFF's Surveillance Self-Defense is the best starting point.
Surveillance Self-Defense →Sources
- 1.
- 2. San Francisco Police Department, Automated License Plate Reader Annual Surveillance Report 2024 · Primary document · · accessed · archived copy
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