(after stating the substance of the bill and answer.) According to the construction which was admitted on the argument, and which seems to me the most fair and obvious, the gravamen of the complainant’s bill is, not that the mayor’s *70court refused to take cognizance of his application for set-off; kut that it decided wrong upon the merits of that application.
There is no doubt that the equity powers of the mayor’s court, and of the court of chancery, are so far concurrent on ' this subject, as that either was completely competent to afford the relief prayed for in this bill. (Barker v. Braham, 2 Bl. Rep. 869. Montague on Set off, 6. Mitchell v. Oldfield, 4 Term Rep. 123. Glaister v. Hewer, 8 Term Rep. 69. 3 Caines' Rep. 190. 1 Johns. Rep. 144. 3 Johns. Rep. 247.) Those courts' are, therefore, co-ordinate, so far as regards this subject of complaint.
The complainant first elected the mayor’s court as his forum, for deciding the question of set-off. The parties there mutually submitted to the jurisdiction of that court; and there was a regular decision upon the merits, denying the set-off.
The question now is, whether the chancellor was bound to disregard the decision of the mayor’s court, and to re-examine and decide upon the merits of the complainant’s bill, as if the relief had been originally sought in his court ?
The general proposition, that courts of concurrent jurisdiction cannot rightfully examine and reverse each other’s decisions, is undeniable: it is founded on principles of obvious policy and convenience; and to permit such clashing and intrusive interference, would be to confound all distinctions between concurrent and appellate jurisdiction.
The inquiry, therefore, is, whether' the case stated in the complainant’s bill falls within the reason and policy of that rule ?
The equity powers of the common law courts extend only to cases which arise incidentally in suits at law: such as relieving bail, granting new trials, and setting off judgments» These powers are exercised, summarily, in the courts of law; and, according to the organization of our judicial system, these -decisions, not forming part of the record, are not the subject of writ of error. Yet, these equitable powers, having been found indispensable to the convenient administration of justice, are now within the established and acknowledged jurisdiction of the courts of law.
If, then, it be admitted that the mayor’s court had rightful cognizance of the subject; that the question of set-off was regularly submitted to that forum, and a decision was thereupon *71made, it seems to me, upon reason and principle, that this case falls within the rule which prohibits one court from reviewing the decisions of another court of competent authority, on the same subject.
Whether the exercise of equity powers, by the mayor’s court is, or ought to be, subject to writ of error, are questions which do not appertain to the court of chancery, and, therefore, have no relation to the question now before this court. Nor do I think it material whether, in technical strictness, the point decided in- the mayor’s court be “ res judicatanor whether the claim for relief in that court, was “ ex debito justitiwj’ or a matter resting “ in discretionAs applied to this case, these distinctions appear to be little more than a dispute about words. Whether a set-off shall be allowed in such a case,' is, indeed, a matter resting in discretion: but this means judicial discretion, regulated by the principles of equity and justice; not a xvanton, capricious, or arbitrary determination of the will.
It is said, the order of the mayor’s court, denying the set-off^ was not final and conclusive in that court, and, therefore, ought not to be held conclusive in chancery. But this is not the test, as between co-ordinate courts of concurrent jurisdiction; because each may re-examine its own decisions, it does not follow that one court can rightfully examine the decisions of another court of equal authority.
Whether the forms and practice of the common law courts/ in regard to their equity poxvers, allow of summary decisions, by entries in their minutes only, or whether they require those proceedings to be entered of record, cannot, in my judgment, form a criterion of chancery jurisdiction.
The party claiming the set-off had his election: he might have originally sought that relief in chancery, subject to appeal; or he was at liberty to seek that remedy by an application to the summary discretion of the mayor’s court, not subject to a writ of error. He chose the latter course ; and the convenience of suitors, and the interests of justice, require, that he should be concluded by his election. A different rule would destroy the comiiy and respect between the co-ordinate tribunals, xvhich are essential to harmony in our judicial system, and highly favourable to the pure administration of justice. Besides, it would be unjust, for xvant of mutuality ; for if the application *72jn the mayor’s- court had been successful, it is admitted that such decision would have been conclusive against the respondent. Is it fit and equitable, that the complainant shall be air lowed to litigate the question of set-off in the court of law, as a mere experiment, whereby he may gain, but cannot lose his object ?
I think the motion for set-off rests on the same footing as a motion for a new trial, as regards the question now before us ; and the opinion of Lord Redesdale, in the case of Bateman v. Willoe, (1 Sch. & Lef. 201.,) is high authority upon that analogous point. It is there decided that the court of chancery will-not grant a new trial, if it has been denied at law; and Lord Redesdale says, “ it is not sufficient to show that injustice has been done, but that it has been done under circumstances which authorize the court to interfere. Because, if a matter has already been investigated in a court of justice, according to the common and ordinary rules of investigation, a court of equity cannot take on itself to enter into it again.’’
There is, however, a class of cases wherein the courts of law, not having equity powers adapted to, or not commensurate with the justice of the case, the court of chancery has rightfully assumed jurisdiction; although courts of law had collaterally held cognizance of the subject; (Bromley v. Holland, 5 Ves. 610. 7 Ves. 3. Rathbone v. Warren, 10 Johns. Rep. 587. ;) but those cases are plainly distinguishable from the present case.
But it is contended, that the complainant’s bill contains new matter, which affords ground for relief in chancery, and which was not the subject of decision in the mayor’s court. The new fact, so relied on, is, that there are several unsatisfied judgments against E. Hart, which were docketed prior to the judgment in favour of the appellant againsj Joel and Ephraim Hart, which fact was not shown upon the application in the mayor’s court.
The bill, however, does not aver that the complainant believes that Ephraim Hart is insolvent; nor is it pretended that the complainant has come to the knowledge of those judgments, since the application to the mayor’s court. The bill does not seek relief against laches, fraud, or mistake; nor is the court of chancery asked to interfere, on the ground of newly discovered evidence. It is not a new fact, but merely an additional item of *73evidence, tending to show the insecurity of Sims on’s judgment against Joel and Ephraim Hart; which additional fact existed prior to the motion for set-off; and, for aught that appears, it was known to Simson, and the evidence of it completely in his power, at the time of his application to the mayor’s court; but of which, it seems, he did not then choose to avail himself.
No doubt, a rehearing may enable a party to come better prepared ; he may give additional evidence, and urge new arguments, upon the point in litigation; but pitiable indeed would be the condition of suitors, if these were deemed sufficient grounds, not merely for a new trial, but for a new suit, in another court of concurrent jurisdiction. Vexation, expense, and delay, would be infinite, under such a rule. Justice, instead of being seated on a stable throne, would become an ignis fatuus, tantalizing and mocking her followers, by continually eluding their grasp. “ Interest reipublicce ut sit finis litiumfi is the maxim for this case. (Greathead v. Bromley, 7 T. R. 455. Schemerhorn v. Weatherhead, 1 East’s Rep. 537.)
The question is not, whether the mayor’s court decided wrong; but whether the chancellor had a right to correct the proceeding of the mayor’s court, if it were wrong.
My opinion is that his honour, the chancellor, properly disclaimed jurisdiction in the case; and that the decree ought to be affirmed.
Van Ness, J., was of the same opinion.
Spencer, J.There are two points for the consideration of the court: 1. Was the appellant entitled to the relief prayed for in his bill, independently of his application to "the mayor’s court of New-York, and had not that application been made? 2. Is the decision of the mayor’s court such a determination as precludes a court of equity from entertaining the question, and affording the relief sought for ?
The chancellor, in assigning his reasons for dismissing the appellant’s bill, has not discussed the first question, nor was it necessary for him to do so. That question has been made, and holding a different opinion on the second point, it is necessary for me to consider both.
The answer admits the judgments as stated, and also the judgments of third persons against the respondent, and that he *74is unable to pay them, and is on the limits of the prison. It does not admit, in terms, the insolvency of Ephraim Hart, but states that the respondent does not believe him to be insolvent; but that, on the contrary, if he should be so fortunate as to recover what is due to him, he would be able to pay all his debts. The answer arraigns the justice of the appellant’s judgment, but principally insists, that the mayor’s court refused to order the set-off. The appellant put in a general replication to the answer. No proofs appear to have been made, other than those arising from the bill and answer.
As to the facts which are to guide this court, we can only consider such as are stated in the bill, and admitted by the answer. The answer being replied to, the allegations set up in it, and which were not an answer to the interrogatories in the bill, must be proved otherwise than by the respondent’s oath. It is a principle, about which there can be no dispute, that matters set Up in an answer, by way of avoidance, and not necessarily drawn forth by the bill, must, after a general replication, be proved» or the defendant cannot avail himself of them. Every thing’ therefore, alleged in the answer, impeaching the justice of the appellant’s judgment, must be laid out of the case. Independently of this principle, I do not think it competent to the respondent to draw in question, collaterally, the effect of the appellant’s judgment.
In my opinion, we are authorized to draw the conclusion from the admissions in the answer, that the respondent was absolute-N ly insolvent, and that Ephraim Hart was extremely embarrassed in his affairs, insomuch that the appellant’s chance of coercing the payment of his judgment, by execution, was almost hopeless. Such a state of facts furnished a strong and substantial basis for the interposition of a court of equity, on the ground of a meditated fraud. Nothing could be more unjust than to leave to the respondent the power of collecting his judgment of the appellant, against which, from the insolvent condition of the respondent, and the embarrassed state of his father, the appellant could not indemnify himself, by collecting any part of his judgment from them; and, although it is difficult to settle precisely the extent of the jurisdiction of the court of chancery, one of its acknowledged and most salutary attributes consists in the power to put a stop to proceedings injurious, or u'nconscientious. I have no hesitation in saying, that chancery *75had original and rightful jurisdiction of the suit, and was fully authorized, by a series of adjudged cases, in issuing a perpetual injunction against the respondent’s suing out, or executing an execution on his judgment, upon the appellant’s entering satisfaction for so much as the respondent’s judgment amounted to, on his judgment; or, which would have produced the same result, decreeing that the respondent should acknowledge satisfaction of record, upon the like terms.
There is no force in the objection that the judgments are not in the same right; it is well settled, “ that although the demands, as being joint and several, are not, strictly speaking, due in the same right, yet if the legal or equitable liabilities or claims of many become vested in, or may be urged against one, they may be set-off against separate demands, and vice versa (Bull. N. P. 336. 2 H. Bl. 587. 4 Term Rep. 123.;) and in some of the cases this was done without any pretence of insolvency in either of the parties.
The objection is equally untenable, that the judgment in favour of the appellant, being for a tort, the respondent’s judgment ought not to be set off, and deducted therefrom, because there is no contribution among trespassers. The respondent owes the appellant the whole of that judgment; and he could enforce it against him alone, if he saw fit.
That the mayor’s court had the power to direct the set-off applied for, cannot be doubted. The supreme court did so in Schermerhorn v. Schermerhorn, (3 Caines' Rep. 190.) In Brewerton v. Harris, (1 Johns. Rep. 144.,) it was refused, because the larger judgment had been obtained in the "common pleas; but so far were we from doubting of the right, that we intimated that the court of common pleas would afford the relief sought for.
In directing a set-off of judgments, courts of law proceed upon the equity of the statute authorizing set-offs; for, confessedly, the case is not within the letter of the act. Their power consists in the authority they hold over suitors in their courts ; and it may be fitly said, that the exercise of the power is the exertion of the law of the courts, rather than any known, express, and delegated power. Suitors may ask the interference of courts of law, in effecting a set-off, not ex debito justitce, but ex gratia curice. In aecourt of equity, and in a case like the present, it is otherwise. It is a power incidental to that court, and has *76been long exercised exclusively ; for it is only within a few ' years that courts of law have undertaken to set off one judgment against another. ,
I am not aware that, thus far, I have advanced any opinion in oppsition to that of his honour the chancellor; but I am under the necessity of differing from him as to the only remaining point. No judge, I am persuaded, ever bestowed more pains and laborious research upon causes coming before him for decision than the present chancellor. This consideration has induced me to as careful an examination of the case as I am able to make, and the result is, that I cannot assent to the opinion, that the decision on the motion made by the appellant in the mayor’s court, ousted the jurisdiction of a court of equity, upon the principle that it was res judicata, or on the ground of comity. This result is founded, not only on the manner of deciding questions of that kind on summary motion, but, as I conceive, on authority. The motion itself was a summary application to the mayor’s court; and it is a fact, well known, that such motions do not admit of that grave discussion and consideration, as questions arising on demurrer, in arrest of judgment, or for a new trial. Again; decisions on summary application can never be thrown into the shape of a record, and become the subject of review in any other court. In the same court these decisions are not considered so final and decisive as to furnish a bar to another and further discussion of the question. Courts, to prevent vexatious and repeated applications on the same point, have rules which preclude the agitation of the same question on the same state of facts: these rules are for the orderly conduct of business, and are not founded on the principle of res judicata. It is not uncommon, in courts of law, to deny a motion one day, and on another to grant it, on a more enlarged state of facts. 1
Upon authority, it seems to me that the decision of the mayor’s court was not decisive of the question. (7 Ves. 14, 15. 5 Ves. 108. Rep. temp. Finch, 472.) Were it necessary to uphold the jurisdiction of the court of chancery in this case, the new fact, stated substantially in the bill, that Ephraim Hart was also insolvent, would seem to put that question beyond doubt; for, certainly, the decision on the summary application ought to have no greater effect in ousting the court of chancery of its jurisdiction than it would have upon the court which made the *77decision; and it appears to me that even that court, on another application, by bringing before it that additional fact, might, and ought to entertain the question a second time.
I perfectly subscribe to the proposition, that the judgment of a court of competent jurisdiction, upon a matter within its cognizance, is final and conclusive, unless appealed from, and reversed or vacated; but this rule, in my apprehension, does not embrace this case, because it has no quality of a judgment.
The jurisdiction of chancery has been narrowed, and very properly so, in many cases. Since courts of law have adop.ed more liberal and enlarged notions, and will grant new trials, when the circumstances of the case satisfy them that injustice has been done, courts of equity, with great propriety, refuse their interference in such cases.
In modern times, the comity due from one court of co ordinate jurisdiction to another, has been better understood, and more liberally extended; and I would not, in the slightest degree, impugn those salutary principles which preclude one court from re-examining, except in the regular method of appeal, or writ of error, the judicial decisions of another court having jurisdiction of the subject matter. The cases cited and relied on by his honour the chanceller, (1 Johns. Cases, 436. 6 Term Rep. 471. 1 Sch. & Lef. 20l.,) meet my most decided approbation; but, in my judgment, the principles adopted in those cases do not apply to a decision upon a summary application, nor to a case where, from the ascertainment of a new fact not brought before the court, on the original application, even the same court might, with entire propriety, hear a new discussion of the question. I do not, therefore, differ from his honour the chancellor in his principles: I dissent from him only in the application of acknowledged principles to this particular case. My opinion, accordingly is, that the decree appealed from, ought to be reversed.
Thompson, Ch. J., and Yates, J., were of the same opinion.
All the senators (except Van Vechten, Allen, Cochean, Hascall, Stewart, and Tibbits, who concurred with Mr. J. Platt,) being of the same opinion, it was, thereupon, ordered, adjudged, and decreed, that the order of the court of chaneery be reversed,* with costs to be taxed, and that the pro*78ceedings be remitted to the court of chancery, to the end that the set-of£ in the pleadings in the cause, may be allowed, and that the same be proceeded upon according to law.
Decree reversed;
For reversing 21, for affirming 8.