ANDREWS, Ch. J.

This is a proceeding by mandamus, and the judgment from which the appeal is taken directs the mayor of the city of Albany to give written directions to the city engineer to notify the owner of the building on Pearl street known as the Albany Female Academy to remove the porch of the building, which the judgment finds projects thirteen feet and four inches into Pearl street, within ten days after receipt of the notice, pursuant to the provisions of section 10, title 13 of chapter 298 of the Laws of 1883, as amended by chapter 398 of the Laws of 1888.

The question whether the porch projected into the street and the extent of the alleged encroachment was litigated on the trial. If the affirmance of the judgment depended on the question whether in fact the alleged encroachment existed, we should have no difficulty. Upon the facts found and proved there can be no reasonable doubt that the porch is an unlawful obstruction in the street and a public nuisance. Although originally built with the consent of the city, the municipality could not legalize the structure so as to bar the public right, and the user, though long continued, is no obstacle to proceedings for its removal. All the remedies, public and private, for the abatement of encroachments in highways or public streets, are open and unaffected by the colorable authority under which the porch was erected, or by acquiescence in the unlawful user. ( St. Vincent's Orphan Asylum v. City of Troy, 76 N.Y. 108, and cases cited.) But the question here is whether, under the provision of the city charter referred to in the judgment, the mayor of the city may be compelled, under the coercion of a writ of mandamus, to direct the city engineer to give the notice therein specified. When such direction is given by the mayor, either voluntarily or by compulsion, the duty imposed on the city engineer is mandatory and imperative. Upon receiving such direction he must give the notice of ten days to the owner, and if the owner neglects or refuses to comply with the notice, he must then cause such removal to be made, in the first instance at the expense of the city, to be reimbursed by an assessment on the property of the owner. The city engineer would have no discretion, but would be bound to act in accordance with the peremptory direction of the statute. Is the authority given to the mayor to initiate these summary proceedings, by directing the city engineer to give notice to the property owner, also a mandatory duty, or was it the intention of the charter to leave it to his judgment and discretion whether this method of enforcing the public right should be pursued? The right to proceed against the mayor by mandamus depends upon the answer to this question. There is no dispute as to the rule of law that a mandamus against a public officer, or a municipality, is a proper remedy to compel the performance of a ministerial duty plainly prescribed, and may be invoked in behalf of any party interested in its performance, on the failure of the officer or public body to do the act or thing required. But where the officer or body is clothed with a discretion, and it may do or omit to do the act or thing according to the judgment of the person or body authorized to act, then a mandamus can only issue to compel a decision, in case of a refusal to decide, and when a decision is made the remedy by mandamus ends. The court cannot on mandamus review the decision made, or compel a decision the other way, because the court may disagree as to the justice or propriety of the conclusion reached. The broad distinction is between duties mandatory and peremptory and those involving discretion and judgment. In the one case the public agent cannot refuse to act, or to do the thing required, and in the other the court is not permitted to substitute its judgment for that of the officer or body clothed by the law with the power to decide. There is sometimes difficulty in determining whether a duty is peremptory or discretionary. Language permissory in form is sometimes construed as imperative in meaning. It is not infrequent that a statute declares that it shall be lawful for an officer or body to do this or that, or that this or that thing may be done, using language which in ordinary acceptation imports permission, and not command, and in many such cases the duty is held to be imperative. It is a question of the real meaning of the legislature to be ascertained from a consideration of the nature of the authority, the character of the public agency, and the public duty involved. For example, it has frequently been held that where authority is given to raise money by taxation for public purposes or to discharge a municipal obligation, the duty to exercise the authority may be imperative, although conferred in permissory language. On the other hand, there are many occasions for vesting in public agencies actual discretion in respect to the exercise of powers conferred, because the legislature cannot always anticipate the circumstances which may call for their exercise, or which may require that they should be held in abeyance. ( People ex rel. v. Fairchild, 67 N.Y. 334; People ex rel. Hammond v. Leonard, 74 id. 443; People ex rel. Francis v. City of Troy, 78 id. 33; Dillon on Municipal Corporations, § 98; High on Extraordinary Rem. §§ 24, 42.)

In the light of these familiar principles we are to consider whether the mayor of Albany had a discretion to refuse to issue the direction to the city engineer, which the judgment below requires him to give. It appears by reference to the charter of Albany (Laws of 1883, chap. 298) that the original section relating to the summary removal of buildings projecting into streets is one of the sections of title 13, entitled "city engineer and surveyor." This title prescribes the duties of that officer, and the section as originally passed contained no reference to the mayor, and conferred upon him no authority or duty, but left it to the engineer and surveyor on his own motion to institute the proceedings (§ 11). This general and unguarded power might lead to very grave consequences, and place upon the city onerous responsibility. The amendment of 1888 (Chap. 398, title 13, § 10) for the first time made the mayor a necessary party to any proceedings instituted for the summary removal of buildings standing upon or encroaching on the streets. The amendment provided that the city engineer "shall, upon the receipt of written directions from the mayor," send written notice, etc. It took from the city engineer the power to institute the proceedings independently of the mayor, which he possessed under the original section, and made the preliminary direction of the mayor essential before any action should be taken by the subordinate officer. It is, we think, quite manifest from the history of this provision, as well as from its language, that it was the intention of the legislature to confide to the mayor the determination whether summary proceedings under that section should be commenced in a given case. There was great propriety in this. The city, if it proceeded to tear down buildings under this section, would do so at the hazard of being able to justify the act by showing that the encroachment in fact existed, and to the extent of such interference. The decision of the mayor would not bind the property owners. The owners whose buildings were threatened with demolition, might upon cause shown to the satisfaction of the court procure an injunction. But they would not be bound to do so, but might await the trial of the right in an action for damages. The city had other remedies by ordinary procedure at law to remove the obstruction, in pursuing which it would incur no hazard. It seems to us that it was the plain intention of the section, as amended, to confide to the judgment and discretion of the mayor the determination of the question whether proceedings should be taken under this section of the charter, and if this is the true meaning of the statute, the court had no power by mandamus to compel him to initiate such proceedings.

We think the situation was not changed by the resolution of the council passed April 15, 1889. That resolution was in form a request by the council to the mayor to take proceedings for the removal of the porch under the section in question. It was adopted in pursuance of the report of the law committee of the council previously made, in which report it was said: "The passage of this resolution will, however, operate simply as a recommendation to the mayor, with whom the matter is discretionary." It is reasonable to suppose from the form of the resolution adopted that it was acted upon in this view. The statute left the matter to the judgment of the mayor, and the council could not change the character of the duty imposed and make that mandatory which under the statute was discretionary. The common council as commissioners of highways might institute proceedings appertaining to their functions as such, but the power to change the statute was not among them.

These views lead to a reversal of the order below. Judgment of Special and General Terms reversed and proceedings dismissed, with costs against relator.

All concur.

Judgment reversed.