The opinion of the court was delivered by

Costs were awarded against the borough of Sea Isle City, in the county of Cape May, upon a certiorari brought to set aside a tax sale and successfully prosecuted by the Sea Isle City Improvement Company. Judgment was ■entered and execution issued therefor. , The sheriff served a copy of the execution upon the defendant as assessor of the borough. Upon such a service an assessor is required by law (Gen. Stat., p. 1421, pl. 34) to assess and levy, in addition to the regular taxes, the amount due upon the execution, but the defendant refuses so to do and sets up, as justification *477in response to a rule for mandamus, that taxes previously assessed against property in the borough belonging to the improvement company are in arrear and unpaid, and that the borough council has offered to credit thereon the amount of the execution.

ISTo enforceable right of set-off is claimed, but it is urged that this court' should recognize the supposed equity and refuse a writ resting in discretion.

The word “ discretion,” when applied to a court of justice, is amplified by Lord Mansfield to mean “ a sound discretion guided by law.” Rex v. Wilkes, 4 Burr. 2539. Even as to-mandamus, the prerogative writ most sparingly used, discretion to deny is not arbitrary, but is guided and limited by fixed principles. Shortt Mand. *223. In this case we are-afforded no legal reason why the relator should be thwarted of his statutory right to collect a judgment against a municipality by compelling resort to the taxing power.

The borough of Sea Isle City, like every municipal corporation, has a legal method to enforce payment of taxes, and that method is exclusive. City of Camden v. Allen, 2 Dutcher 398.

This court cannot create a right of set-off, and if it could it has no power in this proceeding to determine that the taxes claimed are really on relator’s property or that they have-been legally assessed. ■ .

Moreover, the costs awarded on the certiorari belong to the-attorney in that proceeding. There is no proof or presumption that he has been paid by his client.

Applying the analogy of setting off judgments under the equitable power of the court, the lien of the attorney for his-costs should be preserved. In such cases this is always done, and is done irrespective of the priority of the judgments. Examples of such protection where the costs attached to the-later judgment will be found in the following cases: Cole v. Grant, 2 Cai. 105; Perry v. Chester, 53 N. Y. 240.

' We decide that the relator is entitled to a mandamus as-prayed. If the defendant desires to review this decision and *478shall so notify this relator’s attorney within five days, the •case máy be put in the shape of an alternative mandamus, return and demurrer, with a judgment thereon in favor of the relator, with costs. Otherwise, a peremptory mandamus may go, but without costs.