Automated license plate readers (ALPR) are increasingly installed to monitor the movement of people. So we monitor their installation and use.
Where are ALPR installed? Let's find out
We have gathered some of the data from MuckRock FOIA requests for easier exploration:
Law enforcement agencies use ALPR to track the movement of automobiles, typically by placing them at critical intersections in a pattern which makes it difficult to avoid surveillance. There are also mobile units which may be assembled on an as-needed basis.
Once set up, the cameras continuously record when a car passes by, storing the timestamp, license plate, and often metadata such an image of the car, its make and model, and other relevant information. These records are searchable by the owner of the camera, and by others depending on how the network is configured.
It is also possible in some systems (e.g. Flock Safety) to set up automatic surveillance for a given license plate, such that the user is notified whenever that car is seen within their network.
For more information about how often these systems are used and how extensively the data are shared, see resources such as Eyes on Flock which summarize transparency reports from ALPR network operators.