Final answer:
The most important power of the court is judicial review, which grants the authority to declare laws unconstitutional, ensuring that government actions comply with the U.S. Constitution. This power, central to the system of checks and balances, was established in Marbury v. Madison. Despite its significant influence, the court cannot initiate cases and must rely on cases being brought before it.
Step-by-step explanation:
The most important power the court has is judicial review. This power, established by the U.S. Supreme Court in the landmark case of Marbury v. Madison in 1803, allows federal courts to declare state or federal laws unconstitutional. Judicial review is essential to the system of checks and balances within the U.S. government, ensuring that all legislative and executive actions are by the U.S. Constitution.
Through judicial review, the Supreme Court acts as a Constitution-bound arbiter, making it a powerful equal among the three branches of government. The use of this power has evolved since its inception, and while initially described in Federalist No. 78 by Alexander Hamilton as a necessary part of the judicial role, it has led to debates over the extent and limits of the Supreme Court's authority in recent times.
However, it is important to note that the Supreme Court cannot initiate its cases and must wait for cases to be brought before it. Thus, while the power of judicial review is far-reaching, it also has inherent limitations.