Tau, Byron. 2020. U.S. news: DHS’s use of phone data will be probed. Wall Street Journal, Dec 03, 2020. (accessed December 3, 2020).

WASHINGTON — The Department of Homeland Security’s internal watchdog said it would open an investigation into the use of mobile-phone surveillance technologies to track Americans without a warrant, the latest salvo in a debate within the U.S. government over the legality of such techniques.

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The department also buys software from Babel Street, another vendor that sells location-data products, according to public records.

Venntel and Babel Street didn’t respond to requests for comment.

Such data is widely used by the U.S. military and intelligence agencies for intelligence gathering overseas, according to public records and people familiar with the matter, but those agencies are largely barred from domestic monitoring.

You can read the full article here: https://www.wsj.com/articles/homeland-security-watchdog-to-probe-departments-use-of-phone-location-data-11606910402