concurring.
I agree that the district court had ancillary jurisdiction over the police officers’ claim against the township. I also agree that New Jersey law provides a procedural *388mechanism by which the district court, under rule 69, could adjudicate the indemnification claim. Accordingly, because I join in the majority’s discussion of the merits (Part III), I vote to affirm the judgment of the district court. I write separately, however, because I believe that Judge Gibbons’ discussion of ancillary jurisdiction, while conceptually sound in many particulars, cuts too broadly.
Although Judge Gibbons divides his jurisdictional discussion into a garnishment analysis under Rule 69 and a cross-claim analysis under Rule 13(g), I do not believe that the procedural rule alters the basis of ancillary jurisdiction. The issue of jurisdiction is separate from the issue — properly decided by the majority — of whether the rules provide a procedural mechanism by which the court could decide the indemnification issue. See Finkle v. Gulf & Western Mfg. Co., 744 F.2d 1015, 1018 (3d Cir. 1984) (“Although the claims presented in this case were authorized by the Federal Rules of Civil Procedure, we must still decide whether there is federal subject matter jurisdiction over them.”) Although the police officers’ claim must satisfy both the requirements of jurisdiction and of the procedural rules, the Federal Rules of Civil Procedures may neither extend nor contract federal jurisdiction. Fed.R.Civ.P. 82.
As discussed more fully infra, a proper analysis of jurisdiction in this case should flow from the conventional criteria for ancillary jurisdiction not from broad analogies to garnishment or to cross-claims. Because specific applications of ancillary jurisdiction may themselves implicate the limits of federal power, broad analogies, such as those employed by the majority, are problematic. Compare Finkle, 744 F.2d 1015 (allowing exercise of ancillary jurisdiction over plaintiff’s Rule 13(a) counterclaim against a non-diverse, impleaded third party) with Owen Equipment & Erection Co. v. Kroger, 437 U.S. 365, 98 S.Ct. 2396, 57 L.Ed.2d 274 (1978) (rejecting exercise of ancillary jurisdiction over plaintiff’s Rule 14(a) claim against a non-diverse, implead-ed third party).
I.
Judge Gibbons’ opinion appears to assume the broad proposition that a federal court has ancillary jurisdiction over any effort to enforce its judgments regardless of whether the adjudication of the defendant’s claim for funds involves facts and defendants unrelated to the original dispute. Judge Gibbons analogizes such enforcement actions to garnishment. But garnishment proceedings, as the New Jersey example demonstrates, see NJ.Stat. Ann. § 2A:17-63, generally cannot encompass disputed or unliquidated claims, see 6 Am.Jur.2d Attachment & Garnishment §§ 126-27 (1963 & Supp.1986), so they do not involve truly separate litigations. The mere fact that federal courts normally have ancillary jurisdiction over garnishment proceedings does not demonstrate that they also have jurisdiction over disputed enforcement actions against third parties not present in the original action.
Many enforcement actions are not truly ancillary. That the original parties pursue an action to provide the defendant with funds for satisfaction of the original judgment does not itself provide a sufficient nexus to the original dispute. In a converse situation, federal courts have faced the question whether a state court enforcement action is sufficiently separate from the original litigation that it may be removed to federal court if it presents a proper basis for federal jurisdiction. See 1A J. Moore, B. Ringle & J. Wicker, Moore’s Federal Practice 110.167[12. — 3], at 526 (2d ed. 1986) (citing cases). Just as a state enforcement claim may be sufficiently separate from the principal litigation to justify removal upon independent jurisdictional grounds, a federal enforcement claim may be sufficiently separate to prevent a federal court from exercising jurisdiction in the absence of independent jurisdictional grounds.
I can easily imagine a situation where ancillary jurisdiction would be in serious doubt — for example, the post-judgment pursuit of a questionable gambling debt *389allegedly due the defendant from a non-diverse party who was not involved in the principal litigation. This hypothetical action would require the resolution of both factual questions, such as the existence of the contract giving rise to the indebtedness and the potential interposition of an affirmative defense concerning capacity to contract, and legal issues of significant state concern, such as the public policy concerning collection of gambling debts. Under general principles of ancillary jurisdiction, discussed infra, such a claim would probably not be ancillary but would be a separate claim triable only in state court. 4m-bromovage v. United Mine Workers of America, 726 F.2d 972, 989-91 (3d Cir. 1984). Neither do I believe that all claims for indemnification necessarily support ancillary jurisdiction, as the majority explicitly holds. Indemnification claims also may involve complex facts, questions of important state policy, and third parties absent from the principal litigation.
II.
Rather than sanctioning a potentially expansive, fixed rule of ancillary jurisdiction designed to foster implementation of Rule 69, I believe that we should apply conventional principles of ancillary jurisdiction to the particular facts of this case. The primary justification for ancillary jurisdiction is “the judicial reality that [some] multiple claims are most efficiently disposed of in a single proceeding.” Ambromovage, 726 F.2d at 989. Accordingly, the first criterion for ancillary jurisdiction is always whether the ancillary and principal claims hinge on a “common nucleus of operative fact.” Id., citing United Mine Workers v. Gibbs, 383 U.S. 715, 725, 86 S.Ct. 1130, 1138, 16 L.Ed.2d 218 (1966); see also American Law Institute, Study of the Division of Jurisdiction Between State and Federal Courts, § 1313(a), at 28, & commentary, at 208-12 (1969). A court should also inquire whether exercise of jurisdiction would violate a federal policy and whether a balance of prudential factors, such as “convenience, judicial economy ... fairness to litigants and ... interests of federalism,” calls for a federal forum. Ambro-movage, 726 F.2d at 990 & n. 53.
In this case, these prudential factors justify the district court’s exercise of jurisdiction. The Rule 69 proceeding required an analysis of the same factual events at issue in the principal litigation. Even the ultimate determination of whether the policemen were acting in the scope of their duties and were covered by the collective bargaining agreement related to the question in the original litigation of whether the officers were acting under color of state law. Moreover, no federal policy counsels against jurisdiction of the indemnification claim. In sum, many of the same factors that would justify jurisdiction of the indemnification claim if it had been timely asserted as a cross-claim under Rule 13(g) continue to justify jurisdiction over the Rule 69 claim.
The mere fact that jurisdiction would have been proper if the claim were made earlier, however, does not make it proper here. In many situations, the balance of convenience, judicial economy and fairness that generally justifies ancillary jurisdiction might not justify a claim brought after the initial litigation is over.1 For example, a fact-specific, disputed claim against a new, unrelated third party asserted after the end of the principal litigation will rarely *390save judicial resources by being attached to the original litigation because the new party is entitled to relitigate any questions of fact relevant to its liability.
The facts of this case, however, justify jurisdiction despite the late assertion of the indemnification claim. First, interests of convenience and judicial economy are satisfied. The Rule 69 action involves no parties absent in the initial action who are entitled to relitigate factual contentions already resolved in the principal action. To the extent that the new claim involves any factual questions, they are virtually the same as those already contested, and the new claim brought no demand for a jury trial or other significant procedural burden. Thus, the district judge could consider the evidence adduced in the initial proceedings and speed resolution of the indemnification dispute.
Second, interests of fairness counsel strongly in favor of jurisdiction. The record makes plain why the policemen did not assert their cross-claims against the township in the original litigation: the Township’s insurance carrier controlled the lawsuit, and selected and paid counsel for both the Township and the police officers. When the insurance carrier assumed the defense of the policemen, it created the impression that the indemnification clause of the collective bargaining agreement applied. Yet, neither the Township nor its insurance company gave any indication before or during trial that either would disregard the obligation under the collective bargaining agreement to pay a judgment against the police officers. As Judge Barry commented at the hearing to show cause, “There was never any doubt in anyone’s mind in this courtroom, that the Township was going to pick up the freight, and in fact I was advised so in a number of conversations.” Joint Appendix at 99; see also Joint Appendix at 103 (quoted in the Majority Opinion at —.) Under these circumstances fairness also militates in favor of jurisdiction.
III.
Under the facts, adjudication of the enforcement phase of this case involved a common nucleus of operative fact with the underlying claim, impinged on no federal policy, and advanced convenience, judicial economy and fairness. I therefore believe that the district court properly exercised ancillary jurisdiction over the indemnification claim pursuant to the Rule 69 judgment execution procedure; hence I concur in the judgment of the court.
. Judge Gibbons asserts that because there is no time bar on the filing of a cross-claim, jurisdiction is proper in this case. But this argument confuses the requirements of our rules of procedure with the separate requirements of jurisdiction. Furthermore, although there is no fixed time bar to cross-claims, courts still weigh prudential considerations in deciding whether to accept late cross-claims. See 6 C. Wright and A. Miller, Federal Practice and Procedure § 1431, at 169 (1971). Even if I were to apply Judge Gibbons’ analogy to time restrictions on Rule 13(g), and even assuming that cross-claims may be made after settlement of the principal claim, I would still weigh interests of convenience and fairness in deciding whether to permit this constructive cross-claim. However, because I find that Rule 69 provides the procedural mechanism to implement ancillary jurisdiction, I need not consider the alternate procedural mechanism of Rule 13(g).