Davies, J.

—The grounds of this application are that the tax commissioners of the city of New-York have inserted the name of the relators in the assessment roll for the year 1856, and have assessed them for personal estate in the sum of $100,000. This assessment roll has been returned to the supervisors of the county of New-York, who have revised and corrected the same, and estimated and assessed the tax the relators are to pay upon such assessment. For that purpose the supervisors have their annual meeting on the second Wednesday of July in each year (Davies' Laws, 1003, § 23).

By section 27 of the same act, they must cause the corrected assessment roll, with the warrant for the collection of the taxes assessed, to be delivered to the receiver of taxes on or before the first day of September thereafter. After the taxes are assessed, warrant issued and delivered to the receiver of taxes, the supervisors have no further control over the assessment roll, and a mandamus to them to strike the relator’s name from the roll would be entirely nugatory. Their power is spent, and if the writ issued and they were to obey it, it would not stay the receiver of taxes in the execution of the warrant.

That a mandamus should not go under such circumstances has been expressly held in two cases (The People v. Supervisors of Westchester, 15 Barb., 607; The People v. The Supervisors of Greene, 12 Barb., 217). The well-settled rule is recognized by these cases', that a mandamus will not be granted when it would be unavailing from a want of power in the defendants to perform the required duty. This is a prerogative writ which the court may issue or withhold at discretion, and I have no doubt it would be improper to issue it in this case.

The supervisors have the power, if they choose to exercise it, if the application is made to them within six months after the tax-rolls are delivered to the receiver of taxes, to remit or reduce any tax. This is entirely discretionary with them, and they are constituted the judges of the goodness of the cause shown (Davies’ Laws, 1003, § 28). But it seems to me that the relators have a very serious obstacle to remove before they can be relieved of this tax. It is provided (1 Rev. Stats., 416, § 9) *86that if the president or other proper officer of any corporation named in any assessment roll, shall show to the satisfaction of the Board of Supervisors, at their annual meeting, within two days after the commencement thereof, by affidavit to be filed with the clerk of the Board, that such corporation is not in the receipt of any profits or income, the name of such corporation shall be stricken off the assessment roll, and no tax shall be imposed upon it. And the assessment of any moneyed or stock corporation, authorized to make dividends on its capital, from which no such affidavit shall be received, shall be conclusive evidence that such corporation was liable to taxation, and was duly assessed. That life insurance companies are liable to taxation, whether incorporated on the mutual principle or otherwise, on the capital they have actually employed in business as the capital of the corporation, is now well settled (Mutual Insurance Co. of Buffalo v. The Supervisors of Erie, 4 Comst, 442 ; Sun Mutual Insurance Co. v. The Mayor of New-York, 4 Seld., 241; The People on rel. Mutual Life Insurance Co. v. The Board of Supervisors of New-York, 20 Barb., 81). Row the statute has declared, in the most emphatic language, that if the affidavit is furnished as required, the name of the corporation shall be erased from the assessment roll, and no tax imposed upon it.

If it be true, therefore, that this corporation, as is now alleged, at the time this assessment was made, was not in the receipt of any profits or income from the capital employed in its business in this State, then it was the duty of the proper officer of the corporation to have furnished such affidavit, and had the name of the corporation struck from the assessment roll;

If such an affidavit had been furnished, and the supervisors had omitted to discharge their duties in the premises, a writ of mandamus would have been the proper remedy to have compelled its performance.

The statute also requires that this affidavit shall be furnished at the annual meeting when the assessment rolls are revised and corrected, and the tax imposed within two days after the commencement thereof. And this requirement is made for wise reasons. Taxes are laid for the support of the government, and it is the intention of the statutes in reference to this subject, that all real and personal estate, with a few unimportant exceptions, *87should be assessed, and that the taxes should be equally imposed on such assessments. To ascertain such real and personal estate, and the value thereof, we have in this city assessors and tax commissioners, and when they have fully ascertained all such property liable to taxation, and the amount thereof, the assessment rolls are finally transmitted to the Board of Supervisors for correction and revision. They have no power to reduce or increase any valuation, or to add any property, real or personal, to the assessment rolls, or make deductions therefrom, except that given to them by this ninth section, in reference to corporations making the affidavit, and that conferred by the fourteenth section in reference to companies authorized to commute their taxes. The reason for all this is, that a certain or ascertained sum is to be raised for the purpose of the government annually, and this has to be equally apportioned upon the assessed value, and the law intends that they shall be definitely ascertained before the apportionment of the tax is made. With all this caution and effort assessments will be made which ought not to be made, and taxes will be assessed and apportioned which cannot be collected; and the result is, that such deficiencies have to be annually carried forward and added to the taxes of the succeeding year. But in reference to corporations assessed, the statute has declared, in the most explicit language, that the assessment of any corporation from whom no such affidavit as mentioned above shall have been received, shall be conclusive evidence that such corporation was liable to taxation, and was duly assessed. This corporation was called upon, if they desired to escape taxation, to furnish such an affidavit within the time prescribed by law; and not having done so, the statute declares, in the most positive terms, that the evidence of its liability to taxation, and that it was duly assessed, is conclusive, and I am not at liberty to say that it was not. The Court of Appeals, in the case of the Mutual Insurance Company of Buffalo v. Supervisors of Erie (4 Comst., 449), affirm this doctrine in the broadest terms, and I am therefore precluded, by the terms of the statute, and the doctrine of the highest court of the State, from granting the relief sought by the relators.

The motion for mandamus must be denied, with costs ; but if the relators desire it, the same direction or order will be made *88as by Judge Mitchell in the case of The People v. The Board of Supervisors of New-York* (20 Barb., 86).

That order was as follows : “ The motion for a mandamus is denied with ten dollars costs ; but to enable the relators to carry the question further, they may have an alternative mandamus stating all the facts contained in these papers on which this motion is founded, so that the defendants may demur thereto, and let an order be entered denying a peremptory mandamus ; and proceedings may be stayed on the execution until the decision of the general term.”