N.Y. Second Class Cities Law § 165
No action or proceeding shall be maintained to set aside, vacate, cancel, annul, review, reduce or otherwise question, test or affect the legality or validity of any assessment or tax for a local improvement, except in the form and manner and by the proceedings herein provided. If, in the proceedings relative to an assessment or tax, entire absence of jurisdiction on the part of the officers, board or body authorized by law to levy or assess the same or to order the improvement on account of which the assessment was made or tax imposed, is alleged to have existed or in case any fraud or substantial error, other than the errors or irregularities specified in the preceding section, by reason of which substantial damages have been sustained, are alleged to have existed or to have been committed, any party aggrieved thereby, who shall have filed objections thereto within the time and in the manner specified by law therefor, may apply to the supreme court at any special term thereof, held within the judicial district in which the city is situated, for an order vacating or modifying such assessment as to the lands in which he has an interest, upon the grounds in said objections specified, and no other, and upon due notice of such application to the corporation counsel. Each such application shall be made within twenty days after the confirmation of the assessment. Thereupon such court may proceed to hear the proofs and allegations of the parties and determine the same, or may appoint a referee to take the proof and report thereon, or to hear, try and determine the same. If it shall be determined in such proceeding that the officers, board or body had no jurisdiction to make the levy or assessment complained of or to order the improvement, the court may order such assessment or tax vacated. If it shall be determined therein that any such fraud or substantial error has been committed and that the party applying for such relief, has suffered substantial damages by reason thereof, the court may order that the assessment or tax be modified as to such party and as so modified that it be confirmed. A like application may be made to secure a modification or reduction of any such assessment or tax on account of fraud or such substantial error occurring in the performance of the work of the improvement on account of which such assessment or tax is made or levied, and it shall be determined in like manner. If, in any such proceeding, it shall be determined that such fraud or substantial error has been committed, by reason of which any such assessment or tax upon the lands of any such aggrieved party has been unlawfully increased, the court may order that such assessment or tax be modified by deducting therefrom such amount as is in the same proportion to such assessment or tax as the whole amount of such unlawful increase is to the whole amount of the assessment or tax for the improvement. An order so made in any such proceeding shall be entered in the clerk's office of the county in which the city is situated, and shall have the same force and effect as a judgment. The court may, during the pendency of any such proceeding, stay the collection of any assessment or tax involved therein as against the parties thereto. Costs and disbursements of any such proceeding may be allowed in the discretion of the court. No appeal shall be allowed or taken from the order made in any such proceeding, but the determination so made therein shall be final and conclusive upon all parties thereto. No assessment or tax shall be modified otherwise that to reduce it to the extent that the same may be shown by the parties complaining thereof to have been in fact increased in dollars and cents by reason of such fraud or substantial error. In no event shall that proportion of any such assessment which is the equivalent of the fair value or fair cost of the improvement be disturbed for any cause. No money paid on account of any assessment or tax shall be recovered for any cause, except the amount of the excess of such assessment or tax over and above the fair value and cost of the improvement. In case of the failure of any assessment or tax for any cause, the comptroller shall certify such fact to the common council and it shall be its duty to forthwith cause the same to be relevied and reassessed in a proper manner.
N.Y. Second Class Cities Law § 165