Madison is the first of many important opinions issued by Marshall. It set a precedent for the use of “judicial review,” the power of the Supreme Court to determine whether a law is constitutional or unconstitutional. Although the idea of ​​judicial review was not new at the time, the Marbury decision helped establish the role of the judiciary and clarify the role of the Supreme Court within the structure of American government . At the same time, Marshall's opinion appeared impartial to the political aspects of the case, aiming to demonstrate that politics should not interfere with legal decisions. His thoughts on understanding the case come from his belief that the federal judiciary must protect citizens against state governments that go too far, which can be done by declaring laws enacted by state governments.