The statement that best assesses the impact of the cases Marbury v. Madison and McCulloch v. Maryland on the Constitution is: Both cases increased the powers of the federal government.
Marbury v. Madison established the principle of judicial review, thereby enhancing the power of the judiciary in interpreting the Constitution and the laws. McCulloch v. Maryland affirmed the supremacy of federal laws over state laws and expanded the implied powers of Congress, indicating that the federal government has the authority to enact policies necessary to carry out its constitutional responsibilities.