The longest working Chief Justice in Supreme Court history, Marshall ruled the Court for thirty years and was an important part of making the American legal system. His most important addition was judicial review; the power to stop laws that violate the Constitution. Marshall has been called the one that made the judicial branch special and powerful. Marshall also balanced the power between the federal and state government. He made sure the federal law was more powerful than state law and agreed with an expansive reading of the enumerated powers.