Municipal law, to be satisfactory, should be a body of abstract principles capable of being applied impartially to all relevant facts, just as Marshall and Jay held it to be.  Where exceptions begin, equality before the law ends, as I have tried to show by the story of King David and Uriah, and therefore the great effort of civilization has been to remove judges from the possibility of being subjected to a temptation, or to a pressure, which may deflect them from impartiality as between suitors.  In modern civilization, especially, nothing is so fatal to the principle of order as inequality in the dispensation of justice, and it would have been reasonable to suppose that Americans, beyond all others, would have been alive to this teaching of experience, and have studiously withdrawn their bench from politics.  In fact they have ignored it, and instead they have set their judiciary at the focus of conflicting forces.  The result has been the more unfortunate as the English system of jurisprudence is ill calculated to bear the strain, it being inflexible.  In theory the English law moves logically from precedent to precedent, the judge originating nothing, only elaborating ideas which he has received from a predecessor, and which are binding on him.  If the line of precedents leads to wrongful conclusions, the legislature must intervene with a statute rectifying the wrong.  The Romans, who were gifted with a higher legal genius than we, managed better.  The praetor, by his edict, suppressed inconvenient precedents, and hence the Romans maintained flexibility in their municipal law without falling into confusion.  We have nothing to correspond to the praetor.

Thus the English system of binding precedents is troublesome enough in a civilization in chronic and violent flux like modern civilization, even when applied to ordinary municipal law which may be changed at will by legislation, but it brings society almost to a stand when applied to the most vital functions of government, with no means at hand to obtain a corrective.  For the court of last resort having once declared the meaning of a clause of the Constitution, that meaning remains fixed forever, unless the court either reverses itself, which is a disaster, or the Constitution can be amended by the states, which is not only difficult, but which, even if it be possible, entails years of delay.

Yet pressing emergencies arise, emergencies in which a settlement of some kind must almost necessarily be reached somewhat rapidly to avert very serious disorders, and it has been under this tension, as I understand American constitutional development, that our courts have resorted to legislation.  Nor is it fair for us to measure the sagacity of our great jurists by the standard of modern experience.  They lived before the acceleration of movement by electricity and steam.  They could not foresee the rapidity and the profundity of the changes which were imminent.  Hence it was that, in the spirit of great lawyers, who were also possibly men tinged with a certain enthusiasm for the ideal, they began their work by ruling on the powers and limitations of sovereignty, as if they were ruling on the necessity of honest intent in dealings with one’s neighbor.