National intelligence chief James R. Clapper said Thursday that the Foreign Intelligence Surveillance Court had approved two limits on how the government can use huge volumes of data it collects about Americans' phone use.
The new restrictions were among reforms promised last month by President Barack Obama to the controversial anti-terror surveillance program of the National Security Agency.
Under the first change, Clapper said, the massive caches of phone records can be searched only after a court finds that there is "a reasonable, articulable suspicion that the selection term is associated with an approved international terrorist organization."
That limitation will be in place "absent a true emergency," Clapper said without elaboration.
The second change requires that the data query results "be limited within two hops of the selection term instead of three."
That reform means that government investigators can trace a suspicious call only through one intermediary number instead of through two numbers.
The Foreign Intelligence Surveillance Court, which Congress created in 1978 to approve wiretaps and other secret forms of monitoring, granted a motion from the Justice Department on Wednesday to implement the changes, Clapper said.
The DOJ motion and the court order granting it will be posted online after Feb. 17, Clapper said.