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§13.4 Level of Proof Necessary (More Probable Than Not)

The Case:  Bara v. Clarksville Memorial Health Systems, Inc., 104 S.W.3d 1 (Tenn. Ct. App. 2003).


The Basic Facts:  Parents sued hospital and doctor for death of their child alleging defendants mis-diagnosed injuries following an automobile accident and subsequent incorrect and negligent treatment. 


The Bottom Line:


  • “Over the objections of Plaintiffs, the trial court charged the jury in accordance with the defendant’s special request number nine which asserted ‘in order for you to find that the injuries and/or death of Ms. Bara were proximately caused by the negligence of any defendant, the plaintiffs must have proven causation to a reasonable degree of medical certainty.’”  104 S.W.3d at 7.


  • “The actual charge embodying this special request provides: ‘Proof of causation in a medical malpractice case cannot rest on conjecture. The mere possibility of such causation is not enough to sustain the plaintiff’s burden of proof. In order for you to find that the injuries and/or death of Ms. Bara were proximately caused by the negligence of any defendant, the plaintiffs must have proven that causation to a reasonable degree of medical certainty.’”  Id.


  • “Assuming that such a charge to the jury was proper, the same glaring deficiency confronts the jury as has confronted the bench and bar for seventy years.  Nobody undertakes to define the meaning of the term.  Prior to incorporating this special request number nine into the charge, the judge has just finished charging the jury that Plaintiffs have the burden of proving, by a preponderance of the evidence, all facts necessary to prove fault on the part of Defendants.  Then the court specifically defines preponderance of the evidence to mean ‘more likely true than not.’  Then it has charged that if the negligence of a party was ‘a legal cause of the injury or damage’ that party is at fault.  Thus, the two time honored elements lack of ordinary care and legal (proximate) cause have been correctly charged under a ‘preponderance of the evidence’ requirement.  Then on the heels of these imminently correct instructions the jury is told that ‘proof of causation’ (cause in fact and proximate cause?) must be proven, not by a preponderance of the evidence, but ‘to a reasonable degree of medical certainty.’”  Id.


  • “This is the precise bullet that the trial court correctly dodged in Miller v. Choo Choo Partners, L.P., [73 S.W.3d 897 (Tenn. Ct. App. 2001)].  When the defendant challenged the trial court’s refusal to charge the jury as to this ‘reasonable certainty’ element, Judge Susano, for the majority in the Eastern Section of the Court of Appeals, countered:


The defendant’s proposed instruction regarding the requirement that expert testimony on causation be ‘reasonably certain’ embodies a correct principle of law. However, we do not find that it was error not to instruct the jury as to this principle.  That an expert’s testimony is ‘reasonably certain’ is said to be a prerequisite to the admissibility of that testimony.  See Lindsey, 689 S.W.2d at 862.  The admissibility of expert testimony is a matter of law for the court, not the jury.  See McDaniel v. CSX Transp., Inc., [955 S.W.2d 257, 263 (Tenn. 1997)].  The trial court did not err in refusing to give this instruction.


Miller, 73 S.W.3d at 909.”  Id. at 8.


·      “Thus, Judge Susano correctly points out the only justifiable function that ‘reasonable degree of medical certainty’ ever had.  That it is, (under what is even in the admissibility of evidence context of highly questionable utility), a gate keeping question of law under which the trial court decides whether or not a doctor’s opinion is admissible in evidence.  It is not jury charge material and can only lead to confusion.”  Id.


·       “In Volz v. Ledes, 895 S.W.2d 677 (Tenn. 1995)[sic], the supreme court said:


T.C.A. § 29-26-115(a)(3) requires that a plaintiff in a medical malpractice action prove that ‘[a]s a proximate result of the defendant’s negligent act or omission [of accepted community medical standards], the plaintiff suffered injuries which would not otherwise have occurred.’”




·      “This statutory language is simply another way of expressing the requirement that the injury would not have occurred but for the defendant’s negligence, our traditional test for cause in fact.  Kilpatrick v. Bryant, 868 S.W.2d 594, 602 (Tenn.1993).”  Id.


·      “Additionally, causation in medical malpractice cases must be shown as a matter of probability, i.e. more likely than not, or greater than a 50 percent chance, that the plaintiff’s injuries would not have occurred but for the negligent actions of the defendant(s).”  Id.


·      “In Kilpatrick v. Bryant, 868 S.W.2d 594 (Tenn.1993), the supreme court went to great lengths to iterate the difference between causation in fact and proximate cause and to reassert that each was a separate element of negligence.  Said the court:


Causation and proximate cause are distinct elements of negligence, and both must be proven by the plaintiff by a preponderance of the evidence. Bradshaw, 854 S.W.2d at 869; McClenahan v. Cooley, 806 S.W.2d 767, 774 (Tenn. 1991); Smith v. Gore, [728 S.W.2d 738, 749 (Tenn. 1987)].  ‘Causation (or cause in fact) is a very different concept from that of proximate cause.  Causation refers to the cause and effect relationship between the tortious conduct and the injury.  The doctrine of proximate cause encompasses the whole panoply of rules that may deny liability for otherwise actionable causes of harm.’  King, Causation, Valuation, and Chance in Personal Injury Torts Involving Preexisting Injuries and Future Consequences, 90 [Yale L.J.] 1353, 1355 n. 7 (1981).  Thus, proximate cause, or legal cause, concerns a determination of whether legal liability should be imposed where cause in fact has been established.  McKellips v. Saint Francis Hosp., [741 P.2d 467 (Okl. 1987)].  ‘Cause in fact, on the other hand, deals with the ‘but for’ consequences of an act. ‘The defendant’s conduct is a cause of the event if the event would not have occurred but for that conduct.’’  Id. at 470 (quoting Prosser and Keeton, [The Law of Torts], 266 (5th ed.1984)).


Kilpatrick v. Bryant, 868 S.W.2d at 598.”  Id. at 8-9.


·      “Neither Kilpatrick v. Bryant nor Lindsey v. Miami Development Corp., [689 S.W.2d 856 (Tenn. 1985)], involve jury instructions or jury questions but involve rather summary judgment and gate keeping questions of law.  As said in Kilpatrick:


Thus, proof of causation equating to a ‘possibility,’ a ‘might have,’ ‘may have,’ ‘could have,’ is not sufficient, as a matter of law to establish the required nexus between the plaintiff’s injury and the defendant’s tortious conduct by a preponderance of the evidence in a medical malpractice case.  Causation in fact is a matter of probability, not possibility and in a medical malpractice case, must be shown to a reasonable degree of medical certainty.


Kilpatrick, 868 S.W.2d at 602.”  Id. at 9.


·      “This Court addressing newly adopted Tenn[essee] Rule of Evidence 702 made clear that admissibility was the question involved in ‘reasonable degree of medical certainty.’  The expert’s opinion must substantially assist the jury in its determination and the question of what will ‘substantially’ assist the jury is one for the trial court to determine.  The expert’s testimony must satisfy Rule 702 and the threshold question for the court’s determination is whether the witness’ testimony ‘will substantially assist the trier of fact to understand the evidence or to determine a fact in issue.’  The Tennessee standard is much more stringent than its federal counterpart which merely requires evidence from experts which ‘assist the trier of fact’ rather than ‘substantially assist the trier of fact.’  The importance of the court’s task in determining whether the evidence will substantially assist the trier of fact is borne out by the weight given to an expert’s testimony.  ‘Expert testimony is unique because experts are allowed to give an opinion in a particular situation whereas other witnesses are prohibited from giving opinion testimony in areas where expertise is not required.’”  Id.


·      “Numerous Tennessee cases establish a necessary degree of medical certainty to prove


‘A doctor’s testimony that a certain thing is possible is no evidence at all. His opinion as to what is possible is no more valid than the jury’s own speculation as to what is or is not possible.’  ‘The mere possibility of a causal relationship, without more, is insufficient to qualify as an admissible expert opinion.’  Primm v. Wickes Lumber Co., [845 S.W.2d 768, 770-71 (Tenn. Ct. App. 1992) (citations omitted)].”


Id. at 10.


·      “Thus, if the doctor cannot testify as to cause in fact to a reasonable degree of medical certainty, his testimony is not admissible before the jury and if there is no other expert evidence of causation in fact in a medical malpractice case, summary judgment would be proper.”  Id.


·      “In the case at bar, in their special request number nine, Defendants and the trial court have taken out of context the phrase ‘causation in fact is a matter of probability and not possibility, and must be shown to a reasonable degree of medical certainty’ as such phrase is used White v. Methodist Hospital South, [844 S.W.2d 642, 648-49 (Tenn. Ct. App. 1992)]; Kilpatrick v. Bryant, [868 S.W.2d 594, 602 (Tenn. 1993)]; and White v. Vanderbilt University, [21 S.W.3d 215, 232 (Tenn. Ct. App. 1999)] dealing with the admissibility of expert testimony and converted it into a jury charge which is exactly what Miller v. Choo Choo Partners, L.P., [73 S.W.3d 897 (Tenn. Ct. App. 2001)] asserts is not proper.”  Id.


·      “It is noted that in some cases as, for instance, In re: Twining, [894 P.2d 1331, 1336-37 (Wash Ct. App. 1995)], the term ‘reasonable medical certainty’ has been held to mean ‘more likely than not.’  One is compelled to ask under such circumstances why ‘reasonable medical certainty’ continues to exist.  It suffices to say in the case at bar that nowhere is anyone informed that the two terms are synonymous.”  Id.


·      “The Supreme Court of Nebraska made a particularly informative observation a century ago: ‘Altshuler v. Coburn, [57 N.W. 836, 838, (Neb. 1894)] we noted that an attempt to give a specific meaning to the word reasonable is like ‘trying to count what is not a number, and measure what is not space.’’  Gleason v. Gleason, [357 N.W.2d 465, 468 (Neb. 1984)].”  Id. at 10-11.


·      “Unless one can, as a matter of every day common sense, say that ‘reasonable degree of medical certainty’ and ‘more probably than not’ are synonymous terms, the instructions in this case are inconsistent and contradictory and misleading to the jury.  The erroneous charge is not harmless but reversible error.”  Id. at 11.


Other Sources of Note:  White v. Vanderbilt University, 21 S.W.3d 215, 232 (Tenn. 2000) (“The law dictates … that the plaintiff produce evidence showing that it is more likely than not that the defendant’s  negligence cause his or her injuries.”).


Recent Cases:  Ambrose v. Batsuk, No. M2006-01131-COA-R3-CV, 2008 WL 1901207 (Tenn. Ct. App. Apr. 30, 2008) (upholding exclusion of treating physician testimony because doctor was unable to state that the accident more probably than not caused the plaintiff’s physical injuries); Hinson v. Claiborne & Hughes Health Center, No. M2006-02306-COA-R3-CV, 2008 WL 544662 (Tenn. Ct. App. Feb. 26, 2008) (affirming dismissal because plaintiff were unable to refute affidavit by defendant’s medical expert stating that the medical records showed that plaintiffs’ father died from causes unrelated to any act or omission on the part of defendant nursing home or its employees); Stanfill v. Mountain, No. M2006-01072-COA-R3-CV, 2008 WL 427281 (Tenn. Ct. App. Feb. 12, 2008) (upholding summary judgment where plaintiff’s expert’s affidavit was insufficient to establish causation because he only opined as to possibilities); Points v. Thompson, No. M2006-02425-COA-R3-CV, 2008 WL 110103 (Tenn. Ct. App. Jan. 9, 2008) (holding there was material evidence to support jury verdict in favor of plaintiff).


After an accident, many injury victims and their families want more information on the accident and their legal rights. Consequently, many of them have found their way to these pages. While we are happy you are here, please understand Day on Torts: Leading Cases in Tennessee Tort Law was written to be a quick, invaluable reference for Tennessee tort lawyers. While the book provides the leading case for more than 300 tort law subjects and thousands of related case citations, it is not a substitute for personalized legal advice from a qualified lawyer.

Rather than researching these legal issues alone, we urge you to contact one of our award-winning lawyers who can sit down with you, review your case, answer your questions and clearly explain your rights and your options in a no-cost, no-obligation consultation. Our experienced attorneys handle all personal injury and wrongful death cases on a contingency basis, so we only get paid if we win. If for any reason you are unable to come to our office, we will gladly come to you.

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The foregoing is an excerpt from Day on Torts: Leading Cases in Tennessee Tort Law, published by John A. Day, Civil Trial Specialist, Fellow in the American College of Trial Lawyers, recipient of Best Lawyers in America recognition, Martindale-Hubbell AV® Preeminent™ rated attorney, and Top 100 Tennessee Mid-South Super Lawyers designee. Read John’s full bio here.

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