ALBaKY CITY NAT. BANK V. MAHEB. 885 �the legislature can sanction retroactivolysuchproceedings in theassess- ment of a tax as it could not have sanctioned in advance. This assessment was void because the persons subjected to it were deprived of notice, and thereby lest the opportunity to be relieved in wbole or in part from the payment of the tax. The curative act perpetrates the vice whicb was originally fatal to the assessment. It denies the shareholders the right to be heard. It does indeed permit a review by certiorari, but the shareholders are limited to a review upon the single ground that the assessment is at a higher proportionate valuation tban other property on the same roll by the same officers. They are not allowed to challenge the assessment upon the ground of overvaluation generally, nor to show that they sbould have been allowed deductions whicb the laws of the state allow to other tax-payers, or to show that they were not in f act the owners of the property for whicb they were assessed. It is, in eflfeot, a legislative assessment of a tax imposed upon a body of indiyiduals selected out of a general class, without apportionment or equality as between them and the general class, or as between themselves, and without giving them any opportunity to be heard. The legislature cannot impose the whole barden of the state or of a single taxing district upon a portion of the property own- ers of the district. "It is of the very essence of taxation that it be levied with equality and uniformity, and that there should be some System of apportionment." Cooley, Const. Lim. 495. This assessment derives no support from the fact that the tax was originally levied upon all other property holders by a System of apportionment whicb secured uniformity and equality, because these shareholders were excluded from the benefit of that System and are still excluded. They are singled out and each assessed an arbitrary sum upon the assump- tion that each is taxable for a given amount of property, and that such sum represents bis share of the oommon burden, wbile they are denied the right given to all others of obtaining the deductions and corrections allowed by the general system of assessment. As is said in Stuart v. Palmer, 74 N. Y. 183 : "It matters not upon the question of the constitutionality of such a law that the assessment bas, in fact, been fairly apportioned. The constitutional validity of law is to be tested, not by what bas been done under it, but by what may, by its authority, be done." Earl, J., 188. It may be that the tax assessed against the shareholders of complainant is no more onerous than they were required to bear, but this fact does not affect the question of legislative power and cannot give validity to the act. ��� �