The federal department announced late Wednesday that it would no longer solicit bids from private companies to build the database.
Initially, officials said the project would help U.S. Immigration and Customs Enforcement officers ensnare "criminal aliens and absconders." But privacy advocates feared it would also collect location data on millions of law-abiding American citizens.
Officials said the solicitation for bids was posted without the awareness of top department officials and had been canceled. "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," an ICE spokesperson said in a written statement.
The use of license-plate scanners has become a controversial topic in law-enforcement and privacy circles in recent months. With enough location data, government agents could learn the everyday habits of millions of Americans – where they go to the doctor, where they go grocery shopping, who they interact with on a regular basis.
"Where people go can reveal a great deal about them," Catherine Crump, a staff attorney with the American Civil Liberties Union, said before Homeland Security abruptly reversed its course. "... I think Americans have good reason to be concerned about the DHS proposal."
Law enforcement has been using license-plate scanners for several years, and private companies have also been collecting data from scanners. It is unclear how they use and broker that data.
At least 14 states are considering legislation that would "curb surveillance efforts, including the use of license-plate readers," according to the Associated Press.
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