A court filing released Monday revealed that the FBI has employed a secretive authority to oblige Internet and telecommunications firms to hand over customer data.
The data includes individuals' total web browsing history and online purchase records.
Such "national security letters" are used by the FBI to conduct electronic surveillance without the need for court approval.
The filing was made public because of an 11-year-old legal battle in which Nicholas Merrill, founder of hosted service provider Calyx Internet Access, refused to comply with a national security letter he received in 2004. National security letters have reportedly been available as a law enforcement tool since the 1970s, according to Reuters, but their use grew dramatically under the USA Patriot Act.
Merrill's challenge also disclosed that the FBI may use NSLs to gain IP addresses on everyone a suspect has corresponded with. Merrill said the release of the court filing was significant "because the public deserves to know how the government is gathering information without warrants on Americans who are not even suspected of a crime."
Tech companies and privacy advocates generally disapprove of the secretive orders, arguing that they allow the government to examine user content without appropriate transparency or legal oversight.