What was established by Congress in terms of judicial power?

The establishment of a federal court system by Congress is a significant development in the framework of American governance as outlined in the Constitution. This was primarily formalized through the Judiciary Act of 1789, which created the federal court system, including the Supreme Court and lower federal courts. This act was essential in defining the structure and jurisdiction of these courts, establishing their authority to hear cases under federal law and affirming the role of the judiciary as an independent branch of government.

This federal court system was crucial in ensuring that there was a uniform interpretation and application of federal laws across different states, promoting consistency and stability within the legal framework of the nation. By creating this system, Congress laid the foundation for a judicial branch that could act independently and check the powers of the legislative and executive branches, embodying the principle of separation of powers designed in the Constitution. Thus, the correct answer highlights this foundational step in creating a balanced governmental structure that included federal judicial authority.