In the same Senate call, CBP also didn’t comment on whether the Supreme Court’s 2018 decision on Carpenter v. United States applies to its use of commercially-available location data. The ruling prevents law enforcement agencies from obtaining cell-site information without a warrant.

"CBP outrageously asserted that its legal analysis is privileged and therefore does not have to be shared with Congress,” the letter states. “We disagree." The group wants the DHS Office of the Inspector General to investigate the practice and determine whether CBP is breaking the law. An aide for Senator Wyden told Motherboard CBP isn’t stopping its personnel