This brings up the question of whether the evidence will be admissable.
The government lawyer said it would be "difficult" to quantify, but she acknowledged that "an abundance of intelligence" came from the Israeli government.
Such reliance on a foreign intelligence agency poses other obstacles in U.S. criminal court proceedings.
For example, who is likely to testify to validate the intelligence data as evidence?
"If you are talking about Israeli intelligence officials testifying or providing information, then you have serious hearsay problems, serious bias problems," said Georgetown University law professor David Cole.
"And I think it could be very questionable as to whether that evidence could be introduced."