Police officer Dennis Vafier uses a laptop in his squad car to scan vehicle license plates during his patrol of the area in Alexandria, Va. on July 16, 2013. Pablo Martinez Monsivais/AP

The Homeland Security Department has abruptly reversed course and dropped plans to ask a private company to give the government access to a nationwide database of license plate tracking information.

Secretary Jeh Johnson canceled a contract proposal on Wednesday that had been issued last week.

The proposal said Immigration and Customs Enforcement was planning to use the license plate data in pursuit of criminal immigrants and others sought by authorities. The contract notice came amid growing concerns about government surveillance of U.S. citizens but didn't address potential privacy consequences.

Gillian Christensen, an ICE spokeswoman, said the contract solicitation was posted "without the awareness of ICE leadership."

"While we continue to support a range of technologies to help meet our law enforcement mission, this solicitation will be reviewed to ensure the path forward appropriately meets our operational needs," Christensen said.

The department said Johnson has ordered a review of the proposal.

Before the notice was canceled, Christensen said the database "could only be accessed in conjunction with ongoing criminal investigations or to locate wanted individuals."

Law enforcement has been using license plate readers for several years, but privacy advocates have raised concerns that the unchecked collection of such information could allow for the tracking of an average citizen's every movement. Lawmakers around the country, meanwhile, have been wrestling with whether or how to control the collection and use of license plate data.

At least 14 states are considering measures that would curb surveillance efforts, including the use of license plate readers.

License plate readers — essentially cameras that snap rapid-fire pictures of license plates and vehicles as they pass — are in use in a host of locations, by private companies and law enforcement. They can be mounted to police cars, traffic lights or toll booths.

But it's not just the license plate number that gets recorded. The readers also record the date, time and location of the vehicle when the picture was taken.

According to the contract proposal, the government wanted "a close-up of the plate and a zoomed out image of the vehicle."

The Homeland Security Department also wanted instant and around-the-clock access to the records and is asking for whoever wins the contract to make the information available through a smartphone app. It is not clear from the contract notice how long individual records would be kept or what other government agencies may have access to the trove of records.

Jennifer Lynch, a senior staff attorney with the San Francisco-based civil liberties group Electronic Frontier Foundation, said those unknowns represented serious privacy concerns.

"The base level concern is that license plate data is location data, and location data is very revealing," Lynch said. "It can tell you a lot about a person's life: where they go, who they associate with, what kind of religion they practice, what doctors they visit."

In 2012, the American Civil Liberties Union criticized the collection of license plate scanner data and warned that millions of records were being collected with little or no safeguards for people's privacy.

Catherine Crump, an ACLU lawyer, said Wednesday she was pleased to hear that the department has canceled the contract proposal but still worried about that it might be brought back to life at some point.

"While we are heartened that it looks as though the plan is off the table for now; it is still unexplained why the proposal was put forward and why it has been withdrawn," Crump said.

The government's contract proposal was published amid revelations of surveillance programs run by the National Security Agency. Privacy advocates have argued that NSA phone data collection programs and other surveillance programs are gobbling up massive amounts of information about U.S. citizens who have no ties to criminals or terrorists, which the government has said the programs are designed to target.

The Associated Press

