Your car got scanned nearly 4 million times in San Diego last month. The city will show you where. The Sheriff won't.

In a single recent 30-day stretch, automated license plate readers mounted on streetlights in the city of San Diego detected nearly 4 million vehicles. Each one logged the plate, the time, and the location, and fed it into a searchable database that police can query in seconds.

The readers are a kind of passive camera network: when a car drives past, the camera reads its plate and checks it against hot lists of stolen vehicles, missing people, and wanted suspects. A match can ping a patrol officer within seconds. A non-match still creates a record of where that car was, when, and on which street. The systems are made by companies like Flock Safety, one of the country's largest automated license-plate camera vendors, and they have spread from a few hundred cities a decade ago to thousands of jurisdictions today.

San Diego is one of Flock Safety's bigger customers. The city runs 500 license-plate readers, and it publishes the location of every one of them on a public map. The San Diego County Sheriff's Office runs 131 more readers, in the unincorporated areas it patrols and in the contract cities that pay it for service, and does not publish a comparable map. Neither do most of the smaller cities in the region.

Chula Vista runs about 150 of its own readers and has logged 1.25 million vehicles in the same 30-day window, querying the data roughly 1,200 times. Coronado runs 10 readers and logged more than 420,000 vehicles while running 98 searches. La Mesa has 20; Vista has 2. The city of San Diego's footprint is the only one a resident can audit on a map today.

That gap, public map in one place and no map next door, is the local shape of a story that has been playing out nationally for months. Flock Safety has come under sustained criticism as its readers have proliferated. A growing list of cities have canceled their contracts. Activist groups have organized "National Week of Action" rallies, including one that drew marchers through downtown San Diego this month, organized by DeFlock, a group pushing back against ALPR expansion. At a city commission meeting earlier in August, a man in a Darth Vader costume delivered a satirical endorsement of Flock Safety that has since circulated widely online; the Emperor, he said, is a fan.

Underneath the satire, the company has made a substantive change. In a statement reported by the San Diego Union-Tribune, Flock Safety said it was shortening its recommended default data retention from 30 days to 7 days, and tightening rules meant to make it harder to abuse the system. The change is a recommendation to the company's customers, not a binding update in San Diego, where local agencies set their own retention and search rules. The city of San Diego's current default is 30 days, and whether local departments adopt the new 7-day default is a decision each agency still has to make on its own.

So what can a San Diego reader actually do? Start with the city map: it lists every camera and where it sits. If you live in an unincorporated neighborhood or in a smaller city like Chula Vista, La Mesa, Coronado, or Vista, the equivalent map does not exist yet. Local councils have begun debating whether to publish one, and residents have shown up to ask. The cameras are not going away. The question, here as in most of the country, is who gets to see them, who gets to keep the data, and for how long. Right now, in San Diego County, the answer depends on which side of a city limit line you live on.