If Congress or any other department of the Government can ignore the limitations of the Constitution, all distinction between government of "limited and unlimited powers" is done away with. To say that "acts prohibited and acts allowed are of equal obligation" is to deny the very purpose for which our fundamental law was adopted. "The constitution controls any legislative act repugnant to it." Congress cannot alter it by legislation.[390] All this, said Marshall, was too clear to admit of discussion, but he proceeded, nevertheless, to discuss the subject at great length.
There is "no middle ground." The Constitution is either "a superior paramount law" not to be changed by legislative enactment, or else "it is on a level with the ordinary legislative acts" and, as such, "alterable" at the will of Congress. If the Constitution is supreme, then an act of Congress violative of it is not law; if the Constitution is not supreme, then "written constitutions are absurd attempts, on the part of the people, to limit a power in its own nature illimitable." Three times in a short space Marshall insists that, for Congress to ignore the limitations which the Constitution places upon it, is to deny the whole theory of government under written constitutions.
Although the contention that the Judiciary must consider unconstitutional legislation to be valid was "an absurdity too gross to be insisted on," Marshall would, nevertheless, patiently examine it.[391] This he did by reasoning so simple and so logical that the dullest citizen could not fail to understand it nor the most astute intellect escape it. But in the process he was tiresomely repetitious, though not to so irritating an extent as he at times became.
If two laws conflict, the courts must decide between them. Where the Constitution and an act of Congress apply to a case, "the court must determine which ... governs [it]. This is of the very essence of judicial duty.... If, then, ... the constitution is superior to any ordinary act of the legislature," the Judiciary must prefer it to a mere statute. Otherwise "courts must close their eyes on the constitution," and see only the legislative enactment.[392]
But to do this "would subvert the very foundation of all written constitutions." It would be to "declare that an act which ... is entirely void, is yet ... completely obligatory," and that Congress may do "what is expressly forbidden." This would give to the legislature "a practical and real omnipotence, with the same breath which professes to restrict their powers within narrow limits." It would be "prescribing limits, and declaring that those limits may be passed at pleasure." This "reduces to nothing" both the letter and the theory of the Constitution.
That instrument expressly extends the judicial power to cases "arising under the constitution." Must the courts decide such a case "without examining the instrument under which it arises?" If the courts must look into the Constitution at all, as assuredly they must do in some cases, "what part of it are they forbidden to read or to obey?"
Marshall cites hypothetical examples of legislation in direct conflict with the fundamental law. Suppose that Congress should place an export duty on cotton, tobacco, flour, and that the Government should bring suit to recover the tax. "Ought judgment to be rendered in such a case?" Or if a bill of attainder should be passed and citizens prosecuted under it, "must the court condemn to death those victims whom the constitution endeavors to preserve?"
Take, for example, the crime of treason: the Constitution emphatically prescribes that nobody can be convicted of this offense "unless on the testimony of two witnesses to the same overt act, or on confession in open court." The Judiciary particularly are addressed—"it prescribes, directly for them, a rule of evidence not to be departed from." Suppose that Congress should enact a law providing that a citizen might be convicted of treason upon the testimony of one witness or by a confession out of court? Which must the court obey—the Constitution or the act altering that instrument?
Did not these illustrations and many others that might be given prove that the Constitution must govern courts as well as Congress? If not, why does the Constitution require judges "to take an oath to support it"? That solemn obligation "applies in an especial manner to their conduct in their official character." How "immoral" to direct them to take this oath "if they were to be used as the instruments, and the knowing instruments, for violating what they swear to support!" Such contradictions and confusions would make the ceremony of taking the oath of judicial office "a solemn mockery" and even "a crime."
There is, then, said Marshall, no escape from the conclusion "that a law repugnant to the constitution is void," and that the judicial as well as other departments are bound by the Constitution.[393] The application of Marbury and others must therefore be dismissed.