In Marbury v. Madison, which was decided two years after his elevation to the bench, he decided that it was the duty of the court to disregard any act of Congress, and, therefore, a fortiori any act of a legislature of one of the States, which the court thought contrary to the Federal Constitution.
In Cohens v. Virginia, in spite of the contention of Jefferson and the then prevalent school of political thought that it was con trary to the Constitution for a person to bring one of the States of the United States, though only as an appellee, into a court of justice, he held that Congress could lawfully pass an act which permitted a person who was convicted in a State court, to appeal to the U.S. Supreme Court, if he alleged that the State act under which he was convicted conflicted with the Federal Constitution or with an act of Congress.
In M'Culloch v. Maryland, though admitting that the Federal Government is one of delegated powers and cannot exercise any power not expressly given in the Constitution, he laid down the rule that Congress in the exercise of a delegated power has a wide latitude in the choice of means, not being confined in its choice of means to those which must be used if the power is to be ex ercised at all.
It will be seen that in the first two cases he established the Supreme Court as the final interpreter of the Constitution.
The decision in M'Culloch v. Maryland, by leaving Congress unhampered in the choice of means to execute its delegated pow ers, made it possible for the Federal Government to accomplish the ends of its existence. "Let the end be legitimate," said Mar shall in the course of its opinion, "let it be within the scope of the Constitution, and all means which are appropriate, which are plainly adapted to that end, which are not prohibited, but consist with the letter and spirit of the Constitution, are constitutional." If the decision in M'Culloch v. Maryland gave vigour to all Federal power, the decision in Gibbons v. Ogden, by giving the Federal Government control over the means by which interstate and foreign commerce is carried on, preserved the material pros perity of the country. The decision recognizes what the framers of the Constitution recognized, namely that the United States is an economic unit, and that business which is national should be under national, not State, control.
Though for the reasons stated, the four cases mentioned are the most important of his decisions, the value of his work as an ex pounder of the U.S. Constitution is not to be measured by these
cases alone. In all he decided 44 cases involving constitutional questions. Nearly every important part of the U.S. Constitution as it existed before the amendments which were adopted after the Civil War, is treated in one or more of them. The Constitu tion in its most important aspects is the Constitution as he in terpreted it. He did not work out completely the position of the States in the Federal system, but he did grasp and establish the position of the Federal legislature and the Federal judiciary. To appreciate his work, however, it is necessary to see that it was the work not of a statesman but of a judge. Had Marshall been merely a far-seeing statesman, while most of his important cases would have been decided as he decided them, his life-work would have been a failure. It was not only necessary that he should de cide great constitutional questions properly, but also that the peo ple of the United States should be convinced of the correctness of his interpretation of the Constitution. His opinions, therefore, had to carry to those who studied them a conviction that the constitution as written had been interpreted according to its evi dent meaning. They fulfilled this prime requisite. Their chief characteristic is the cumulative force of the argument. The ground for the premise is carefully prepared, the premise itself is clearly stated; nearly every possible objection is examined and answered; and then comes the conclusion. There is little or no repetition, but there is a wealth of illustration, a completeness of analysis, that convinces the reader, not only that the subject has been adequately treated, but that it has been exhausted. His style, reflecting his character, suits perfectly the subject mat ter. Simple in the best sense of the word, his intellectual pro cesses were so clear that he never doubted the correctness of the conclusion to which they led him. Apparently from his own point of view, he merely indicated the question at issue, and the inexor able rules of logic did the rest. Thus his opinions are simple, clear, dignified. Intensely interesting, the interest is in the argu ment, not in its expression. He had, in a wonderful degree, the power of phrase. He expressed important principles of law in language which tersely yet clearly conveyed his exact meaning. Not only is the Constitution interpreted largely as he taught the people of the United States to interpret it, but when they wish to express important constitutional principles which he enunciated they use his exact words. Again, his opinions show that he ad hered closely to the words of the Constitution ; indeed no one who has attempted to expound that instrument has confined himself more strictly to an examination of the text. In the proper, though not in the historical, sense he was the strictest of strict constructionists, and as a result his opinions are practically devoid of theories of government, sovereignty and the rights of man.