(dissenting).
In my judgment the District Court should not have afforded a second opportunity to contest the issue of fault in this collision after the same parties, Yankee Lines and Kimmel’s administratrix, had had opportunity and occasion to con*647test that very issue in a Pennsylvania state court which had decided against the administratrix.
In simplified statement the essential facts are these. A fatal accident occurred on a Pennsylvania highway. A vehicle owned by A, the present defendant Yankee Lines, collided with a vehicle driven by B, of whose estate the present plaintiff is administratrix. B was killed and a passenger in his car was injured. The passenger sued both A and B for negligent injury in a Pennsylvania court. A jury made special findings that both A and B were negligent. The trial judge sustained the finding of B’s negligence and entered judgment against his estate. However, the court concluded that the finding of A’s negligence was not supported by the evidence and accordingly entered judgment n. o. v. holding A not liable. No one appealed.
In the meantime the same accident had been made the subject of the present action in the United States District Court wherein B’s administratrix sued A for damages charging A’s negligence as the responsible cause of the death of blameless B. A tried to assert the Pennsylvania proceedings and judgment as a bar, but the court ruled that the facts could be reexamined and accordingly permitted trial in regular course. The federal jury found that A had been negligent and that B was blameless. It is from judgment pursuant to that finding that the present appeal is taken.
Since federal jurisdiction is based on diversity of citizenship, the availability of the defense of res judicata is determined in accordance with the law of the forum, Pennsylvania. Hartmann v. Time, 3 Cir., 1948, 166 F.2d 127; see Angel v. Bullington, 1947, 330 U.S. 183, 67 S.Ct. 657, 91 L.Ed. 832. Thus, we all agree that this case is to be decided as if it were a suit in a second Pennsylvania state court after the prior Pennsylvania decision.
Possible exceptions irrelevant to this case aside,1 the general rule is clear. The proscription against relitigation of an identical issue by a party to the prior litigation concludes the rights inter se only of those parties who were adversaries in the prior action. Restatement, Judgments, Section 82; see 1 Freeman, Judgments, 1925, at 918, cases cited. The highest court of Pennsylvania recognizes that this conception of adversaries may include parties both of whom are aligned as defendants in the overall lawsuit. See Simodejka v. Williams, 1948, 360 Pa. 332, 62 A.2d 17; Pittsburgh & L. E. R. Co. v. Borough of McKees Rocks, 1926, 287 Pa. 311, 317, 135 A. 227, 229. The Simodejka opinion expressly approves the Restatement position. The unsettled question is whether the situation of such co-defendants as A and B in the earlier suit here makes them adversaries within the meaning of this rule. Thus, our difference of opinion is limited to the application of an agreed principle to particular circumstances. For that reason, I think the citing of the Restatement rule and the cases which approve it places our problem in focus but does not solve it.
Simodejka v. Williams, supra, is our starting point. That litigation also arose out of a highway collision and involved a prior action by an injured third person in which the drivers of both colliding vehicles became defendants. However, the original complaint named only driver A as defendant. A thereupon brought B into the case as a third-party defendant, with a view to enforcing contribution by B if the plaintiff should recover. The plaintiff recovered against both A and B. Later A sued B for personal injuries suffered in the same accident. In these circumstances the Supreme Court of Pennsylvania held that as between A and B all rights and obligations arising out of the accident were foreclosed by the judgment in the first suit.
*648Procedurally, the Simodejka case differs from ours in only one respect. A and B are original defendants here while A brought B into the litigation as an additional defendant there. The majority regard that difference as decisive, pointing out that the Simodejka opinion cites and distinguishes situations where co-defendants in a first action have been permitted to litigate the same subject matter in a second suit between themselves. Actually, after noting dissimilarities in some of these cases, the Simodejka opinion disposes of them generally with the observation that “in all but one of them, the suits were brought against co-defendants, who, so far as appears, were not parties adverse to each other”. The reasoning seems to have been that the procedure and legal relations of each situation will determine whether co-defendants in a first action are adversaries for purposes of res judicata. I do not' read the opinion as meaning that all original co-defendants are in one category, while the added defendant situation stands as a different category.
It is true that in Chenger v. Peccan, 1951, 88 Pa.Dist. & Co. 186, .the Court of Common Pleas for Washington County interpreted the Simodejka decision as limited to the situation of defendant and additional defendant and refused to apply res judicata as between original co-defendants such as we have here.2 The Court of Common Pleas emphasized a comment, accompanying Section 82 of the Restatement of Judgments, that “where a person is injured by the concurrent negligence of two tortfeasors who are joined in one action, the fact that each of them attempts to show that the other was solely responsible for the accident or that the other alone was negligent does not make .the issue of negligence res judicata in subsequent proceedings between them * * * ” It will be noted, however, that the Restatement merely states that “the. fact each of them attempts to show that the other was solely responsible” does not make the issue of negligence res judicata between them. If that be conceded, the decisive question still remains in cases like ours whether they were adversaries in that the action determined some liability between the defendants which depended upon the fault or blamelessness of each in the accident. It is that criterion upon which we think the Supreme Court of Pennsylvania caused the Simodejka case to turn.
If my analysis is correct, it is necessary in .the present case to discover whether any element,of A’s claim against B, whether a right to recover for original injury or a right of contribution to damages sustained by a third person, was comprehended by the first suit. Under Pennsylvania law the answer to this question is clear.
In Pennsylvania the duty of contribution between joint tortfeasors is a statutory obligation. Act of June 24, 1939, P.L. 1075, § 1, 12 P.S. § 2081. Originally an equitable obligation, this duty is enforceable in the very litigation in which a third person has successfully recovered judgment against the joint tort-feasors. Anstine v. Pennsylvania R. Co., 1945, 352 Pa. 547, 43 A.2d 109, 160 A.L. R. 981.
Thus, if A and B had both been found liable in the first suit here the Pennsylvania judgment would have been attended by an enforceable obligation of contribution. As the case was actually decided, A was held liable and B exonerated. But had A felt aggrieved by this judgment and the consequent loss of contribution, he could have appealed, not only from the judgment against him, but also from the judgment exonerating B. Schwartz v. Jaffe, 1936, 324 Pa. 324, 188 A. 295; Hair v. Ference, 1945, 352 Pa. 164, 42 A.2d 535. Of course it was A’s right at trial to present evidence of B’s fault and liability. See Frank v. W. *649S. Losier & Co., 1949, 361 Pa. 272, 274-277, 64 A.2d 829, 830-831. The Pennsylvania decisions emphasize the existence of these rights to contest an issue and to appeal a decision as important considerations in determining the reach of estop-pel by judgment. See Lloyd v. Barr, 1849, 11 Pa. 41, 49; Williams v. Lumbermen’s Insurance Co. of Philadelphia, 1938, 332 Pa. 1, 3-6, 1 A.2d 658, 659-660. But I think it is the adversary status of the defendants created by the issue of contribution which is most important in making the adjudication of fault binding between them.
I also observe that the majority’s reliance upon Hassenplug v. Victor Lynn Lines, Inc., D.C.E.D.Pa.1947, 71 F.Supp. 70, 71, affirmed per curiam by this court, 163 F.2d 828, seems misplaced. There the District Court ruled that res judica-ta did not apply because the issue of due care adjudicated in the first suit was different from that presented in the second. And the court was careful to add that, had there been a prior adjudication of the same issue, “the Pennsylvania courts might feel that this plaintiff’s suit should be barred by that verdict, as establishing the defendant’s lack of negligence.”
More generally, the Supreme Court of Pennsylvania has indicated a disposition favorable to the basic policy which supports the application of res judicata in the present situation. In the early case of Lloyd v. Barr, supra, involving a suit between endorsers of a note after the holder had recovered judgment against both of them, the court had this to say about the underlying policy:
“But wherefore put a party to new proof of that which has once been judicially ascertained, after full opportunity to controvert it? Between co-defendants, as well as in the case of antagonist parties, the public tranquillity requires, that having been once fairly tried, further agitation of the same subject be forbidden.” 11 Pa. 41, 52.
And this broad view was reasserted in Hochman v. Mortgage Finance Corp., 1927, 289 Pa. 260, 263, 137 A. 252, 253.
“The thing which the court will consider is whether the ultimate and controlling issues have been decided in a prior proceeding in which the present parties actually had an opportunity to appear and assert their rights.”
All of these considerations lead me to conclude that, as a matter of Pennsylvania law, the plaintiff in the present action was bound by the adjudication of fault in the earlier state litigation. Accordingly, I think the defendant was entitled to judgment n. o. v.
. The issue which divided this court in Bruszewski v. United States, 3 Cir., 1950, 181 F.2d 419, is not reached here.
. We take that decision into account although we are not hound by it. King v. Order of United Commercial Travelers, 1948, 333 U.S. 153, 68 S.Ct. 488, 92 L.Ed. 608.