Whеre a plaintiff settles with one of several joint tortfeasors, New York General Obligations Law § 15-108(a) provides that its claim against the remaining tort-feasors is reduced by the greater of: (1) the amount paid for the release; (2) the amount stipulated in the release; and (3) the released tortfeasor’s equitable share of the plaintiffs damages.
2
N.Y. Gen. Oblig. Law § 15-108(a). The New York Court of Aрpeals has held that while the first two reductions are available at any point before final judgment is entered, the third is lost where a defendant fails to seek apportionment of liability until after a jury’s liability verdict.
See Whalen v. Kawasaki Motors Corp., U.S.A.,
BACKGROUND
Appellants filed this action to recover damages sustained during a three-vehicle collision on the New Jersey Turnpike on December 30, 1998. Appellants were passengers in a car owned аnd operated by Brian J. Ruzalski that was struck from behind by a tractor-trailer owned by D.P. Gallimore & Sons (“Gallimore”) and driven by William S. McLeod. A third vehicle, a tractor-trailer owned by R. Byrd Trucking Company and operated by Rudolph Byrd and Charles Curry (collectively, the “Byrd Defendants”), was directly behind the Gal-limore tractor-trailer. According to a report prepared by the New Jersey Police, thе Byrd Trucking vehicle collided with the Gallimore tractor-trailer, forcing it into the rear of Ruzalski’s Chevrolet Tahoe.
Shortly after the Schipanis filed this diversity action, they settled with the Byrd Defendants for $35,000.
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The Schipanis then moved for summary judgment against Gallimore, arguing that it was negligent as a matter of law for violating New York Vehicle & Traffic Law § 1129(a), which prohibits drivers from following vehicles “more closely than is reasonable and prudent.” In its response, Gallimore did not move to amend its answer to assert a § 15-108 defense and raised no defenses to its liability. Gallimore’s sole argument was that Appellants did not suffer “serious injuries” as required by New York law. The district court (Johnson, J.) rejected that argument and granted the Schipanis’ motion for summary judgment, holding that Gallimore “fail[ed] to make a shоwing sufficient to establish the existence of an element essential to that party’s case.”
Schipani v. McLeod,
No. 00-CV-4343,
In February 2005, Judge Poliak recused herself, and the inquest was assigned to Magistrate Judge Gold. At a May 2005 conference, Judge Gold ordered supplemental briefing on “set-off for prior settlement amounts [and] defendant’s] right to apportionment of liability.” 5 In those papers, Appellants argued that Gallimore had an opportunity to request an apportionment of liаbility before Judge Johnson, but lost it by failing to do so before summary judgment was entered. Appellants also contended that Judge Gold’s consideration of apportionment exceeded his authority to “determin[e] damages.” Galli-more, on the other hand, submitted that it could still seek apportionment because § 15-108 rights cannot be waived “prior to trial.”
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Judge Gold agreed with Gallimore, holding that the decision granting summary-judgment was “a finding of liability and not an apportionment of that liability.”
See Schipani v. McLeod,
No. 00-CV-4343,
The Schipanis appeal from that judgment, contending, among other arguments, that Magistrate Judge Gold erred in permitting an apportionment of liability after summary judgment. We agree.
DISCUSSION
I
In
Whalen v. Kawasaki Motors Corp., U.S.A.,
By failing to seek apportionment against Kawasaki, Robinson foreclosed any possibility of the jury determining Kawasaki’s equitable share of the fault, and in that respect foreclosed use of that prong of the statute’s benefits. Section 15-108(a), however, affords the nonsettling defendant the greatest of three modes of setoff, and the remaining two — the amount stipulated or paid by the settling defendant — were still properly available to Robinson, notwithstanding its failure to put before the jury the question of Kawasaki’s equitable share of fault.
Id.
at 292,
Neither the New York Court of Appeals nor any of the departments of the Appellate Division has considered whether the right to an apportionment is forfeited with the entry of summary judgment on liability.
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Nonetheless, we have littlе difficulty holding that it is. To date, only one court has faced this exact issue squarely. In
Chubb & Son Inc. v. Kelleher,
No. 92 CV 4484,
That holding finds support in the decisions of New York’s appellate courts. The Court of Appeals has notеd that “apportionment of fault is a component of the liability determination.”
Bryant v. State,
Gallimore’s argument to the contrary conflates two commonly confused legal concepts — negligence and liability. Negligence is a necessary — but not sufficient— condition for liability. The Court of Appeals has described negligence as “the failure to employ reasonable care — the care which thе law’s reasonably prudent man should use under the circumstances of a particular case.”
McLean v. Triboro Coach Corp.,
Yet the law also recognizes that not every injury has only one cause. Thus, when multiple tortfeasors “act concurrently or in concert to produce a single injury, they may be held jointly and severally liable,”
Ravo v. Rogatnick,
Thеse principles are clearly illustrated in this ease. When the Schipanis moved for summary judgment on
liability,
they had to demonstrate both that Galli-more was negligent and that its negligence was a substantial cause of the collision. Gallimore’s negligence was predicated on its violation of New York Vehicle
&
Traffic Law § 1129(a).
See Schipani,
Judicial economy is not the only factor leading us to conclude that Gallimore for
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feited its opportunity to apportion liability. Although both federal and New York state courts allow liberal amendments of pleadings,
see
Fed.R.Civ.P. 15(a)(2); N.Y. C.P.L.R. 3025(b), neither permits an amendment that would prejudice the other party,
see Ruotolo v. City of N.Y.,
Gallimore is correct that § 15-108 was enacted “to ensure that nonsettling tort-feasors are not required to bear more than their equitable share of liability.”
Apple v. Jewish Hosp. & Med. Ctr.,
II
Appellants also contend that the district court erred in failing to award prejudgment and postjudgment interest. In their complaint, Appellants clearly demanded all “interest, ... costs and disbursements of this action.” The district court’s failure to include both forms of interests in its judgment was error.
In a diversity case, state law governs the award of prejudgment intеrest.
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See Baker v. Dorfman,
In contrast, postjudgment interest is governed by federal statute. 28 U.S.C. § 1961(a) states that “[¡Interest shall be allowed on any money judgment in a civil case recovered in a district court.... Such interest shall be calculated from the date of the entry of the judgment.” Because we have consistently held that an award of postjudgment interest is mandatory,
see, e.g., Westinghouse Credit Corp. v. D’Urso,
Ill
Finally, Appellаnts submit that the court erred in failing to award them any damages for loss of services. In his opinion, Judge Gold awarded “Frank Schipani $115,000, and Olga Schipani $55,000, for their
past and future pain and suffering,” Schipani,
We express no view on whether Appellants are entitled to damages for loss of services, but remand for clarification. The court’s opinion awarding damages is susceptible to multiple interpretations. It could mean that Appellants were not entitled to loss of services damages, although it did not explain why. It could also mean that its damage awards included pain and suffering and loss of services damages. However, the opinion expressly states that thе figure is for “past and future pain and suffering” and does not reference loss of services. To resolve this ambiguity, we remand to the district court for clarification.
CONCLUSION
For the foregoing reasons, we VACATE in part the judgment of the district court and Remand for further proceedings consistent with this opinion.
Notes
. In its entirety, the statute provides;
When a release or a covenant not to sue or not to enforce a judgment is givеn to one of two or more persons liable or claimed to be liable in tort for the same injury, or the same wrongful death, it does not discharge any of the other tortfeasors from liability for the injury or wrongful death unless its terms expressly so provide, but it reduces the claim of the releasor against the other tortfeasors to the extent of any amount stipulated by the release or the covenant, or in the amount of the consideration paid for it, or in the amount of the released tortfeasor’s equitable share of the damages under article fourteen of the civil practice law and rules, whichever is the greatest.
N.Y. Gen. Oblig. Law § 15-108(a).
.Because many cases use "forfeiture” and "waiver” interchangeably, we believe that "forfeiture” is the correct terminology here, because it refers to a litigant’s "failure to make the timely assertion of a right,” while "waiver” refers to a "litigant’s
intentional relinquishment
of a known right.”
Patterson v.
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Balsamico,
. Appellants never pursued their claims against Ruzalski and McLeod which were subsequently dismissed with prejudice.
See Schipani v. McLeod,
No. 00-CV-4343,
. Pursuant to 28 U.S.C. § 636(c)(1), the parties consented to a trial before Magistrate Judge Gold, and agreed to have all issues decided on their submitted papers.
. While this case might, at first blush, be a candidate for certification to the New York Court of Appeals, neither party advocated certification. Moreover, "existing authority” enables us to “predict[] on a reasonable basis how the New York Court of Appeals would rule if squarely confronted with this issue.”
McCue v. City of N.Y. (In re World Trade Ctr. Disaster Site Litig.),
. We find Appellants’ argument that allowing
any
offset would be prejudicial under
Whalen
to be unconvincing. Their only asserted prejudice is that Gallimore waited too long to seek an offset. However,
Whalen
makes clear that a party may seek to amend its answer to seek a setoff of the amount paid or stipulated for a release "at any time, even after trial, provided that the late amendment does not prejudice the other party.”
Whalen,
