Final answer:
The Court's primary power is judicial review, which allows it to declare laws unconstitutional, as established by the case Marbury v. Madison. This power is a critical check on the other government branches, but the Court cannot enforce its own decisions.
Step-by-step explanation:
The only real power of the Court is judicial review. This significant power allows the Court to invalidate state or federal laws by deeming them unconstitutional, as established in the landmark Supreme Court case Marbury v. Madison in 1803. Though it was not expressly provided in the original Constitution, the judiciary has used this power to act as a check on the other branches of government.
Despite the considerable influence that judicial review grants, it is important to note that the Supreme Court cannot enforce its decisions, relying on the executive and legislative branches for the implementation of its rulings. This separation ensures that no single branch of government has too much power, maintaining a balanced system of checks and balances.
Overall, while the power of judicial review is substantial, it is used with restraint; the Court has struck down a relatively small number of laws in comparison to the many that have passed through Congress over the years.