Israel thinks they can get away with everything they do. They have good reason to think it, as AIPAC and even Congressional treason has been protecting them for decades. It made them so bold that they started to bite the hand that's been feeding them, and in a brazen manner. So, Pollard must remain behind bars. Not only so it'll send a message to Israel, but also because he still has highly sensitive information that hasn't been declassified.
Chairman of U.S. Joint Chiefs of Staff says Iran deal lowers near-term atomic arms risk (Reuters)
from the article: Former Mossad chief: Iran far from achieving nuclear bomb