Litt was asked multiple questions about how surveillance and law enforcement agencies use section 215 to track terrorists. He declined to directly answer the questions posed by panel moderator Ellen Nakashima, a Washington Post reporter, saying specific methods were classified.
"The question is, is this a valuable counterintelligence and counterterrorism tool?" he said. "It is, clearly. It's not true that we could do the same thing under other authorities. There are kinds of records you could not get."
When Nakashima asked what kinds of records the NSA could no longer collect, Litt declined to name them. "I can't talk about them," he said.
Nakashima later asked Litt if the NSA, in the past year, had found any valuable information related to a terrorism investigation through its phone records collection program.
"So I will answer that question with a one-word answer and not take any followups," Litt said. "Yes."
Even with calls for more transparency, the NSA will "never" reveal how it obtained information about a particular terrorist suspect by searching a specific set of records, he said. Those kinds of techniques are classified, he said.
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