They are upholders of falsehood and they make wealth by unfair means. They get bribed into spying. If they come to you asking to judge among them, the choice to accept or reject their request is yours. You have the right to disclaim jurisdiction since they have not yet accepted the Qur'an and they have the Torah. If you disclaim jurisdiction they cannot harm you at all. However, if you decide to judge among them, do so equitably. Allah loves the equitable.