Police around the U.S. who use automatic license plate recognition systems, commonly called ALPR, report increases in productivity, arrests, and recoveries of stolen vehicles, says the St. Louis Post-Dispatch. The American Civil Liberties Union is concerned that the systems are "increasingly becoming a tool for routine tracking and surveillance,” says the ACLU's Anthony Rothert. The group is “looking at possible legislation to balance legitimate law enforcement purposes [ ]  with privacy.” He said only two states, Maine and New Hampshire, currently limit the use of such data.

There has been talk of limiting the length of time data are stored. Some places keep data 30 days. Some have separate standards, depending upon whether the vehicle was wanted. St. Louis keeps its records for one year, based on a poll of other departments. The International Association of Chiefs of Police sees a distinction separating vehicle information from personally identifiable information, such as names, dates of birth or fingerprints. The vehicle data are collected in public areas with no expectation of privacy, the group says.