Diehl is not sufficient to overcome the inference of negligence suggested by the evidence adduced by the plaintiff.
Cassano v. Hagstrom, 5 N.Y.2d 643, 187 N.Y.S.2d 1, 159 N.E.2d 348, rearg. denied, 6 N.Y.2d 882 (1959), which was not cited by the United States Attorney, does not require a contrary result. The plaintiff in Cassano alleged that her lingual and chordia tympani nerves had been severed as the result of the negligence of the dentist who removed her lower left wisdom tooth. Plaintiff's "whole theory of the action" was that the defendant had severed the two nerves "by improperly allowing his drill to penetrate the lingual periosteum which lies between the extracted tooth and these two nerves." Id. at 645. There was "no evidence direct or circumstantial that the instrument used by the defendant came near these nerves," and the defendant "swore not only that he did not cut these nerves but that he did his work on the other side of the tooth, that is, between the gum and the cheek, and did not drill through the tooth and out the other side." Id.
More significantly, aside from the absence of any evidence that the nerves were severed by improper use of the drill, plaintiff's expert in Cassano gave confusing testimony as to the possible cause of plaintiff's paraesthesia. Specifically, he testified that plaintiff had a "degeneration or destruction" of the lingual nerve and that he was certain that the condition could only come from a "severance or destruction or degeneration" of the nerves. Id. at 645. The testimony pointing to "the degeneration of these nerves" as the cause of plaintiff's paraesthesia suggested "the possibility that the condition of the nerves might have been caused nontraumatically." Id. The Court of Appeals held that, where there is evidence that an injury could have been sustained even if due care was exercised, a plaintiff cannot prevail without evidence from which an inference of negligence may be drawn. Because a narrow majority found such evidence lacking in the record, the Court of Appeals affirmed the dismissal of the complaint.
The present case is distinguishable from Cassano in several material respects. There is no dispute here that the lingual nerve was traumatically severed by Dr. Diehl when he extracted plaintiff's wisdom tooth. Tr. 7. Indeed, while impairment of the lingual nerve can be "caused nontraumatically," only a traumatic severance would account for paraesthesia following the extraction of the third molar. See Mozsary & Middleton, supra, at 415-16. More significantly, instead of trying to isolate the precise act of Dr. Diehl that severed the lingual nerve, which is simply not possible, plaintiff relies on circumstantial evidence that was not present in Cassano and that supports an inference that negligence may have been the cause of plaintiff's injury -- evidence that the chance of severing the lingual nerve in the absence of negligence is "infinitesimal" and the fact that the tooth was extracted by a resident in training without supervision.
While this evidence is sufficient for plaintiff to prevail under the New York standard for determining the sufficiency of the evidence, that standard is arguably more stringent than the federal standard. See, 9 Charles A. Wright & Arthur R. Miller, Federal Practice and Procedure, § 2528, at 567-570 (1971). Under the latter standard,
when a district judge is confronted with only two conflicting inferences, each of which he regards as equally probable, and there is no other possible explanation of the event, that, itself, strongly indicates that other judges and other reasonable men might rationally regard the one inference as more probable than the other.
Wratchford v. S.J. Groves and Sons Co., 405 F.2d 1061, 1067 (4th Cir. 1969); see also, N.L.R.B. v. Marcus Trucking Co., 286 F.2d 583, 592 n.8 (2nd Cir. 1961). Accordingly, where the record suggests only two equally probable causes for an injury, the trier of fact is free to choose either one. The inference of negligence here is more compelling than the inference that the nerve was severed because of its anomalous location. At the very least, however, each of these inferences is "equally probable." Thus, under the prevailing federal standard, the evidence is sufficient to allow the submission of the case to the trier of fact and to sustain a verdict for the plaintiff.
Nor is the application of the federal standard precluded by the fact that New York law determines whether a cause of action lies against the United States. See, 28 U.S.C. § 1346(b) (1988). As Chief Judge Haynsworth observed in the context of a diversity case:
The rule as to the sufficiency of the evidence is not bound up with the primary rights and obligations of the parties. In a diversity case, state law defining and limiting those primary rights and obligations must be applied under the Erie doctrine, enabling members of society prudently to plan and conduct their affairs, whether their conduct will later be called into question in a state or a federal court. A choice of a rule as to the quantum of proof necessary to support the submission of a case to a jury plays no role in the ordering of the affairs of anyone. It is not the kind of rule which must inexorably find its governance in a diversity case in the corpus of state law. Indeed, . . . there is little in this situation to support the choice of the state rule as opposed to the federal.
Wratchford, 405 F.2d at 1065-66. Accord, Foster v. Ford Motor Co., 616 F.2d 1304, 1309 & n.10 (5th Cir. 1980); 9 Wright & Miller, supra, at § 2525; cf. Donovan v. Penn Shipping Co., 429 U.S. 648, 649, 51 L. Ed. 2d 112, 97 S. Ct. 835 (1977) ("The proper role of the trial and appellate courts in the federal system in reviewing the size of jury verdicts is, however, a matter of federal law."); Toth v. Yoder Co. 749 F.2d 1190, 1194 & n.2 (6th Cir. 1984) (questioning prior precedent applying state law to determine sufficiency of the evidence); But see, Kudelka v. American Hoist & Derrick Co., 541 F.2d 651, 654 (7th Cir. 1976) (applying state standard). This analysis applies with equal force to causes of action under the FTCA. See, Shumaker v. United States, 714 F. Supp. 154, 158 (M.D.N.C 1988); Denaux v. United States, 572 F. Supp. 659, 662 (D.S.C. 1983).
I conclude that plaintiff has established a prima facie case sufficient to shift the burden of explanation to the defendant and that the explanation offered by the defendant is insufficient to overcome the evidence that plainly points to negligence as the cause of the plaintiff's paresthesia. Accordingly, I find for the plaintiff on the issue of liability.
Edward R. Korman
United States District Judge
Dated: Brooklyn, New York
January 11, 1993