OLR Research Report

April 23, 2001





By: Jack J. Burriesci, Legislative Fellow

You asked for general information on license plate readers used by U.S. Customs officials at border crossings.


License plate readers (LPRs) are part of a joint technology initiative between the U.S. Customs Service and the Immigration and Naturalization Service (INS). They are used at various Mexican and Canadian border crossings. LPRs are designed to automatically read front and rear license plates of vehicles entering and leaving the country. Prior to adopting this technology, inspectors manually entered license plate information into a computer for processing.

The U.S. Customs Service has a contract with Perceptics to install the LPR system. The cost is approximately $87,000 per inbound lane and $93,000 per outbound lane. When the contract expires in September 2002, LPRs will be operational at all Southern and at most Northern border crossings.


LPR systems convert the picture of a license plate to data that includes the vehicle's alphanumeric license plate, state or province of origin, the date and time, and the location. The system sends the information to the Interagency Border Inspection System, where checks are done against the Treasury Enforcement Communications System and National Criminal Information Center (NCIC), as well as various INS databases. If matches are found, customs officers are notified by the system within three seconds after the LPR's initial plate reading. This alerts officers if there is a lookout for a stolen vehicle, wanted felon, custom's fugitive, or armed and dangerous criminal associated with the vehicle. Also, how many times the vehicle crossed a border in the last 72-hours is displayed.

U.S. Customs Service reports that 90% of all plates are read and inputted accurately. LPR reads and queries plates against the databases in one second. To achieve this speed and accuracy, the system is programmed to read only the most common plate types at a particular port.


In 1993, the U.S. Customs Service signed a development contract with Perceptics of Knoxville, Tennessee (a wholly-owned subsidiary of Northrop Grumman Corporation) to install a LPR system for 57 inbound lanes and 14 outbound lanes at various ports of entry in California, Maine, Minnesota, and Washington. The LPRs were first installed at all 24 northbound lanes at the San Ysidro, California port of entry in 1997.

In 1998, the U.S. Customs Service signed a $29 million agreement with Perceptics to install LPRs at an additional 246 inbound and 128 outbound lanes at 19 Northern border and 34 Southern border crossings. The cost of the system is approximately $87,000 per inbound lane and $93,000 per outbound lane. According to the U.S. Customs Service, when the contract expires in September 2002, LPRs will be operational at all Southwestern border crossings and at most Northern border crossings.

The contact person at Perceptics is Roger Leach. He can be reached at (865) 671-9311, or on the Internet at