why should the judiciary have the power to use judicial review
Judicial review is a process under which executive and (in some countries) legislative actions are subject to review by the judiciary. A court with judicial review power may invalidate laws and decisions that are incompatible with a higher authority; an executive decision may be invalidated for being unlawful or a statute may be invalidated for violating the terms of a written constitution. Judicial review is one of the checks and balances in the separation of powers: the power of the judiciary to supervise the legislative and executive branches when the latter exceed their authority. The doctrine varies between jurisdictions, so the procedure and scope of judicial review may differ between and within countries.