Under Chief Justice Marshall, the US Supreme Court became a major player in American government for the first time, far more important than anyone could possibly have envisaged. After arrogating to itself the power of judicial review in Marbury v Madison (1803) the Court came to occupy a central position in American civic life, one it has yet to relinquish to this day.
The overall jurisprudence of the Marshall Court can be seen as closely aligning with the Federalist agenda, complete with a more flexible interpretation of the Constitution. Not surprisingly, Jefferson and other leading Republicans looked upon the judiciary as a Federalist bastion, attempting to achieve through the courts what they palpably failed to do in the 1800 Presidential election. Despite the conspiratorial tenor of the Republicans' political rhetoric there was more than a grain a truth in their suspicions. Marshall had, after all, been appointed by President Adams, who described him as his "gift" to the American people, and was himself a staunch Federalist.
Right throughout the lengthy course of his Chief Justiceship, Marshall put his Federalist principles into action, giving judicial force to the principle of a strong federal government asserting its supremacy over the states. Under Chief Justice Marshall, a state law was struck down as unconstitutional for the very first time, in the case of Fletcher v Peck (1810).
As part of their desire to build a strong federal government, the Federalists advocated the establishment of a central bank. This position was further consolidated at the judicial level in McCulloch v Maryland (1819) in which the Court held that attempts by the Maryland state legislature to impose a tax upon a branch of the Second Bank of the United States were unconstitutional.
The Marshall Court also proved itself to be a redoubtable defender of the Union against the remotest possible threat of secession. In Cohens v Virginia (1821) a relatively trivial criminal case regarding the legality of a federal lottery metamorphosed into a full-blown clash between the advocates of states' rights and Federalism. The General Assembly of Virginia rose in fury, not just denying the Supreme Court's jurisdiction in the case, but even making not so veiled threats to secede from the Union.
Despite the growing threats and anger from the Southern states Marshall stood firm, affirming once again the supremacy of Federal over state law. This principle, combined with the establishment of judicial review is undoubtedly the Court's greatest legacy. Yet in the long run such a bald assertion of centralized power did nothing to quell the growing tensions between federal and state governments that would come to a tragic head forty years later.