That which is consonant to, and agrees with, the consti- tution. Laws made in violation of the constitu- tion are null and void, and it is now well. established that it is the function of the, courts so to declare them in any case com- ing before the court, which involves the question of their constitutionality. The presumption is always in favor of the con- stitutionality of a law, and the party alleg- ing the opposite must clearly establish it. A part of a law may be unconstitutional, whilo there is no such objection to the re- maining parts, and in this case all of the law stands, except that part which is un- constitutional. This power of the courts to declare a law unconstitutional can only exist where there is a written constitution. No such power is possessed by the English courts, and an act of parliament is abso- lutely conclusive and binds everybody when once its meaning is ascertained. But, where a written constitution exists, it is the expression of the will of the sovereign power, and no body which owes its exist- ence to that constitution (as does the legis- lature) can violate this fundamental ex- pression of the will of the people. It was originally doubted whether the courts pos- sessed this power, even where a written constitution exists, but it is now estab- lished beyond doubt. The question may arise with regard to both state and United States laws considered with reference to the United States constitution, and with regard to state laws also as considered in reference to the state. No important ques- tion of law has ever been approached with more caution, examined and discussed with more deliberation and finally determined more conclusively, than that of the exist- ence of this judicial power. It arose as early as 1792, on an act conferring powers upon the judges which were alleged to be not judicial, but a decision was avoided by repeal of the statute; see 2 Dall. 409; but the question arising in another case, the act was declared unconstitutional; see. 13 How. 40, 52, n.; the question was again raised in 1798 and not decided: 8 Dall. 386; and later it was stated from the bench as the general sentiment of the bench and bar that the power existed; 4 Dall. 194. But in 1803 the question was directly raised in a famous case recently much discussed in legal periodical literature, and the power and duty of the court to declare an act un- constitutional were declared in an opinion by Marshall, C. J., in what Kent terms "an argument approaching to the precision and certainty of a mathematical demonstra- tion; " 1 Kent 453; in that case the actual decision was against the jurisdiction, and therefore no law was declared unconstitu- tional, but the reasoning of the opinion is the basis of the rule afterwards applied and firmly settled; the question was next seri- ously raised and finally settled by the rea- soning of Marshall, C. J., in 6 Wheat. 264; Marbury v. Madison, 1 Cra. 187; prior to this decision the question had been raised and decided in favor of the power of the courts in New Jersey, 4 Halst. 427, 440, 444; Virginia, 4 Call 1, 185; 2 Va. Cas. 20; Wythe 211; in South Carolina, 1 Bay 252; 1 Mar- tin, N. C. 42; in Rhode Island, Pamph. J. B. Varnum, Providence, 1787; and it was raised in New York in a case argued by Hamilton; Hamilton's Works, vol. 5, 115; vol. 7, 197. In 12 S. & R., Gibson, C. J., in a dissent- ing opinion, was of opinion that the right of the judiciary to declare a legislative act unconstitutional does not exist, unless ex- pressly stated; but that it is expressly given by the clause in the federal constitution which provides that the constitution shall be the supreme law of the land, etc. The same judge in 2 Pa. 281 said to counsel that he had changed his opinion for two reasons: -the late convention of Pennsylvania by their silence sanctioned the pretensions of the court to deal freely with the acts of the legislature; and he was satisfied from ex- perience of the necessity of the case. The power has been exercised by the su- preme court of the United States in the fol- lowing cases: - Dall. 409; 18 How. 40, 52; 1 Cra. 137; 2 Wall. 561; 4 id. 333; 8 id. 603; 9 id. 41, 274; 11 id. 113; 18 id. 128; 17 id. 322; 92 U. S. 214; 95 id. 670; 100 id. 82; 103 id. 168; 106 id. 629; 109 id. 8; 116 id. 616; 27 id. 540; 158 id. 601, the last being the Income Tax cases in 1895. During the same period the power was exercised by that court with respect to state or territorial stat- utes in one hundred and eighty-two cases. The discussion of the subject has been re- cently revived by an article on the Income Tax cases in the Am. L. Rev. for July-Au- gust, 1895, characterizing the exercise of the power in question as "without consti- tutional warrant" and "based only on the plausible sophistries of John Marshall, and another by the same writer on the case of Marbury v. Madison, characterizing the doctrine as an "unconstitutional usurpa- tion of the lawmaking power by the federal courts;