What precedent was set by Marbury v. Madison in 1803?

The precedent set by Marbury v. Madison in 1803 established the authority of judicial review, which allows the Supreme Court to determine the constitutionality of laws and acts of government. This landmark case affirmed the principle that it is the duty of the judiciary to ensure that no laws or executive actions violate the Constitution, effectively giving the courts the power to nullify laws that are found to be unconstitutional. This established a critical balance of power among the branches of government, ensuring that the judiciary has a role in upholding the Constitution as the supreme law of the land. The significance of this ruling cannot be understated, as it solidified the judiciary's role in checking the other branches of government and protecting individual rights against governmental overreach.