It is supposed to review legal cases appealed to it from lower courts and decide if the Law as applied in the lower courts has been correctly applied. And, to determine if the defendents rights have been compromised in the legal process. That is all that the Supreme Court is allowed to do. Of course, it would be a much easier job if Israel had a Constitution and a Bill of Rights for its Citizens to serve as a standard for their Supreme Court to use for a standard. Then they would not have to wing it on every decision.
from the article: Israeli Justice Ministry bypassing the High Court