Download the worksheet (.pdf)
This worksheet was developed for the Second Report of the Axon AI and Policing Technology Ethics Board.
Automated License Plate Readers (“ALPRs” for short) are one of the most widely used law enforcement systems in existence. Although the adoption of ALPRs has been rapid and widespread, it has happened with too little public oversight.
ALPRs are camera systems that record license plates, as well as the time and place of where the license plate was scanned. ALPRs often are capable of taking in much more than license plates, including the surrounding scene, and even images of drivers and passengers. ALPRs can be mounted almost anywhere: light poles, overpasses, police cars, private tow-trucks, or even run on smart phones.
Many police departments use ALPRs in patrol cars. The ALPR alerts officers if it scans a vehicle whose license plate is in the system, perhaps because the car was reported stolen or is associated with someone with an outstanding warrant.
Besides being used to alert law enforcement to vehicles of interest, the information they collect can be stored away for future reference. Thus, if the police want to know where a vehicle has been at different times, they can consult the stored license-plate database.
ALPRS offer several potential benefits for law enforcement:
ALPRs can help locate missing children or adults through the use of Amber or Silver alerts.
ALPRs can help officers track down more stolen cars by increasing the efficiency with which plates are checked.
ALPRs can help locate people wanted for investigation of serious crimes, including witnesses and suspects.
ALPRs may help remove individual officer discretion from police stops, potentially leading to more equitable law enforcement and criminal justice outcomes.
However, unregulated use of ALPRs can lead to serious issues, including:
ALPR errors can cause the police to stop the wrong vehicle or wrong person.
ALPR-aided enforcement can worsen racial and socioeconomic disparities, particularly when used to enforce low-level offenses or generate revenue through fines and fees.
ALPR data can be used to reveal details about a person’s life, leading to privacy concerns.
ALPRs can be used in ways that chill First Amendment liberties (such as monitoring all the cars parked outside a particular place of worship) and threaten Fourth Amendment rights by allowing law enforcement and private companies to track your location over time.
Unfortunately, because of lack of data and study, we know very little about how large the benefits or costs are—all the more reason every community should do its best to be informed about how its law enforcement is using ALPRs.
10 Questions To Ask Your Local Law Enforcement Agency
1). Is your agency using Automated License Plate Readers (ALPRs)?
How long have they been in use, and how many do they have?
Are they mobile (on police cars) or fixed (on light poles, etc.)
2). Did the public or elected officials have An opportunity to provide input before the Agency acquired or deployed ALPRs?
Who was consulted about the decision to purchase ALPRs?
Did the agency weigh the benefits and costs of using ALPRs before purchasing the equipment?
3). Has your state or municipality passed any laws governing the use of ALPRs?
Do these laws regulate use, transparency, data-retention limits, reporting or audits?
Is your agency in compliance with all applicable laws?
4). Where did your agency acquire the ALPRs it is using, and under what terms?
Are the contracts publicly available?
Is there a non-disclosure agreement barring public disclosure of certain ALPR functions?
Who owns and retains rights to the ALPR data?
5). Does the agency have an ALPR use policy? Is it publicly available?
Who is authorized to use ALPRs and under what conditions?
Do certain functions require supervisory approval, such as searches of historical data?
6). What types of offenses does the agency enforce using ALPRs?
Is ALPR-use limited to serious crimes (e.g., auto theft, Amber alerts) or are they used for low-level offenses (e.g., traffic, immigration violations, outstanding fines and fees)?
On what basis will the agency add a license plate to its alert list (or “hot list”)?
7). What protections are in place to keep ALPRs from being used in a way that has a disparate racial or socioeconomic impact?
Where are ALPRs deployed, and does it result in unequal surveillance of some communities?
What demographic data is being tracked to allow the public to audit the use of ALPRs?
8). What types of data does your agency retain from ALPRs?
Does the agency keep only the records of license plate characters, or does it retain the video or other related images, include the surrounding area and pictures of the drivers?
Is the data cross-referenced against other databases (e.g., gang or criminal history databases)?
9). How long does your agency retain ALPR data?
Does the agency keep scan data for 7 days, (30 days, 90 days, a year, etc.) or does your agency scan plates for live alerts only, without retaining the information, absent evidence of a crime?
Do different rules govern your agency’s use of ALPR data when accessing historical data beyond a certain period of time, such as requiring a warrant to run a search?
10). Does your agency share data with or access data from any other law enforcement agency or private party? Under what terms?
Does your agency share its ALPR scans with, or incorporate scans from, private companies (e.g., tow trucks, private investigators, debt collectors, etc.)?
If so, under what agreements, and how are outside parties accountable for handling your data?