The courts have occasionally gone even further afield, and have professed to deduce certain powers of the legislature from the sovereignty inherent in the national government. In its last decision on the legal tender question, a majority of the Supreme Court seems to have placed upon this ground, though with special reference to the section enabling Congress to borrow money, its affirmance of that competence of Congress to declare paper money a legal tender for debts, which the earlier decision of 1871 had referred to the war power. This position evoked a controversy of wide scope, for the question what sovereignty involves belongs as much to political as to legal science, and may be pushed to great lengths upon considerations with which law proper has little to do.
The above-mentioned instances of development have been worked out by the courts of law. But others are due to the action of the executive, or of the executive and Congress conjointly. Thus, in 1803, President Jefferson negotiated and completed the purchase of Louisiana, the whole vast possessions of France beyond the Mississippi. He believed himself to be exceeding any powers which the Constitution conferred; and desired to have an amendment to it passed, in order to validate his act. But Congress and the people did not share his scruples, and the approval of the legislature was deemed sufficient ratification for a step of transcendent importance, which no provision of the Constitution bore upon. In 1807 and 1808 Congress laid, by two statutes, an embargo on all shipping in United States ports, thereby practically destroying the lucrative carrying trade of the New England states. Some of these states declared the act unconstitutional, arguing that a power to regulate commerce was not a power to annihilate it, and their courts held it to be void. Congress, however, persisted for a year, and the act, on which the Supreme Court never formally pronounced, has been generally deemed within the Constitution, though Justice Story (who had warmly opposed it when he sat in Congress) remarks that it went to the extreme verge. More startling, and more far-reaching in their consequences, were the assumptions of federal authority made during the War of Secession by the executive and confirmed, some expressly, some tacitly, by Congress and the people.14 It was only a few of these that came before the courts, and the courts, in some instances, disapproved them. But the executive continued to exert this extraordinary authority. Appeals made to the letter of the Constitution by the minority were discredited by the fact that they were made by persons sympathizing with the Secessionists who were seeking to destroy it. So many extreme things were done under the pressure of necessity that something less than these extreme things came to be accepted as a reasonable and moderate compromise.15
The best way to give an adequate notion of the extent to which the outlines of the Constitution have been filled up by interpretation and construction, would be to take some of its more important sections and enumerate the decisions upon them and the doctrines established by those decisions. This process would, however, be irksome to any but a legal reader, and the legal reader may do it more agreeably for himself by consulting one of the annotated editions of the Constitution. He will there find that upon some provisions such as art. I, § 8 (powers of Congress), art. I, § 10 (powers denied to the states), art. III, § 2 (extent of judicial power), there has sprung up a perfect forest of judicial constructions, working out the meaning and application of the few and apparently simple words of the original document into a variety of unforeseen results. The same thing has more or less befallen nearly every section of the Constitution and of the seventeen amendments. The process shows no signs of stopping; nor can it, for the new conditions of economics and politics bring up new problems for solution. But the most important work was that done during the first half century, and especially by Chief Justice Marshall during his long tenure of the presidency of the Supreme Court (1801–35). It is scarcely an exaggeration to call him, as an eminent American jurist has done, a second maker of the Constitution. I will not borrow the phrase which said of Augustus that he found Rome of brick and left it of marble, because Marshall’s function was not to change but to develop. The Constitution was, except of course as regards the political scheme of national government, which was already well established, rather a ground plan than a city. It was, if I may pursue the metaphor, much what the site of Washington was at the beginning of this century, a symmetrical ground plan for a great city, but with only some tall edifices standing here and there among fields and woods. Marshall left it what Washington has now become, a splendid and commodious capital within whose ample bounds there are still some vacant spaces and some mean dwellings, but which, built up and beautified as it has been by the taste and wealth of its rapidly growing population, is worthy to be the centre of a mighty nation. Marshall was, of course, only one among seven judges, but his majestic intellect and the elevation of his character gave him such an ascendency, that he found himself only once in a minority on any constitutional question.16 His work of building up and working out the Constitution was accomplished not so much by the decisions he gave as by the judgments in which he expounded the principles of these decisions, judgments which for their philosophical breadth, the luminous exactness of their reasoning, and the fine political sense which pervades them, have never been surpassed and rarely equalled by the most famous jurists of modern Europe or of ancient Rome. Marshall did not forget the duty of a judge to decide nothing more than the suit before him requires, but he was wont to set forth the grounds of his decision in such a way as to show how they would fall to be applied in cases that had not yet arisen. He grasped with extraordinary force and clearness the cardinal idea that the creation of a national government implies the grant of all such subsidiary powers as are requisite to the effectuation of its main powers and purposes, but he developed and applied this idea with so much prudence and sobriety, never treading on purely political ground, never indulging the temptation to theorize, but content to follow out as a lawyer the consequences of legal principles, that the Constitution seemed not so much to rise under his hands to its full stature, as to be gradually unveiled by him till it stood revealed in the harmonious perfection of the form which its framers had designed. That admirable flexibility and capacity for growth which characterize it beyond all other rigid or supreme constitutions, is largely due to him, yet not more to his courage than to his caution.17
III. We now come to the third question: How is the interpreting authority restrained? If the American Constitution is capable of being so developed by this expansive interpretation, what security do its written terms offer to the people and to the states? What becomes of the special value claimed for rigid constitutions that they preserve the frame of government unimpaired in its essential merits, that they restrain the excesses of a transient majority, and (in federations) the aggressions of a central authority?
The answer is twofold. In the first place, the interpreting authority is, in questions not distinctly political, different from the legislature and from the executive, amenable to neither, and composed of lawyers imbued with professional habits. There is therefore a probability that it will disagree with either of them when they attempt to transgress the Constitution, and will decline to stretch the law so as to sanction encroachments those authorities may have attempted. In point of fact, there have been few cases, and those chiefly cases of urgency during the war, in which the judiciary has been even accused of lending itself to the designs of the other organs of government. The period when extensive interpretation was most active (1800–1835) was also the period when the party opposed to a strong central government commanded Congress and the executive, and so far from approving the course the court took, the dominant party then often complained of it.
In the second place, there stands above and behind the legislature, the executive, and the judiciary, another power, that of public opinion. The president, Congress, and the courts are all, the two former directly, the latter practically, amenable to the people, and anxious to be in harmony with the general current of its sentiment. If the people approve the way in which these authorities are interpreting and using the Constitution, they go on; if the people disapprove, they pause, or at least slacken their pace. Generally the people have approved of such action by the president or Congress as has seemed justified by the needs of the time, even though it may have gone beyond the letter of the Constitution. Generally they have approved the conduct of the courts whose legal interpretation has upheld such legislative or executive action. Public opinion sanctioned the purchase of Louisiana, and the still bolder action of the executive in the Secession War. It approved the Missouri Compromise of 1820, which the Supreme Court thirty-seven years