It must be borne in mind that the relator applied for a peremptory writ, and did not offer to take an alternative one. The facts upon which the rights of the litigants must be determined are not disputed. It is agreed that S. P. Dinsmore & Co. published 27,726 lines of official matter upon the order of the mayor and comptroller, for which the firm has been paid $6,931.33, at the rate of 25 cents a line, and gave a release of all demands against the city. The city admits that the firm published 110,721 lines upon the order of its mayor alone, for which the city has refused to pay. The firm brought an action against the city to recover for this work, and was defeated because the comptroller did not join with the mayor in ordering the work. Under this state of facts the statute quoted was passed, and the principal question involved in this appeal is whether the statute is mandatory or permissive. In case the language of a statute authorizes a public body or a public officer to do an act, using the word “may,” and the act authorized relates to the interests of the public, or to the rights of persons, or if the act authorized be to promote justice, the word “may” is generally considered to mean “shall,,r and the statute is deemed mandatory, and not permissive. People v. Supervisors of Otsego Co., 51 N. Y. 401; People v. Supervisors of Livingston Co., 68 N. Y. 114; Sedg. St. Law (2d Ed.) 375. This is a well-settled rule of construction, and the cases wherein it is laid down are referred to in the above authorities, and it is unnecessary to cite them again. But when the rule is invoked in aid of a personal right the right must be an existing legal one, and not one which the board or officer is by the statute authorized to create. Gilmore v. City of Utica, 121 N. Y. 561, 24 N. E. 1009; Buffalo & B. P. Road Co. v. Commissioners of Highways, 10 How. Pr. 239; Turnpike Road Co. v. Miller, 5 Johns. Ch. 101; Sedg. St. Law (2d Ed.) 375 et seq.; Potter’s Dwar. St. 220; and End. Interp. St. § 313. In Gilmore v. City of Utica, supra, it is said that, before this rule of construction will be applied in aid of a public interest or of a private right, “there must be a definite, plain public interest, or a vested, well-defined private right, and then it will very justly be supposed that the legislature meant to subserve or protect the public interest, or to give or secure the private right.” The limitation that the statute must relate to an p-gj sting private right, before “may” shall he construed to mean “shall,” is as firmly settled as the general rule first above stated.
The statute under consideration does not relate to a public interest, and it is conceded by the relator that prior to the statute (chapter 568, Laws 1888) he had no existing legal right to recover for the services rendered. It had been so held by the supreme court in an action