State Supreme Court Affirms Exclusion of Experts' Inferential Opinions

Follow our train of thought: we have posted about the misuse of the differential diagnosis concept, as plaintiff experts morph it from an accepted tool for deciding what is wrong with a patient to a method for explaining why and how the patient suffered his injury/illness.  Now, three computer experts sought to opine that a software flaw prevented a health monitor alarm from sounding, claiming their methodology was just "like a medical differential diagnosis"!  Fortunately, the South Carolina Supreme Court rejected that attempt last week.  See Graves v. CAS Medical Systems Inc., No. 27168 (S.C., 8/29/12).

Their doctor ordered that the plaintiffs use a monitor manufactured by CAS to track their infant child's breathing and heart rates as a precaution. The monitor was designed to sound an alarm, if the subject were to experience an apneic, bradycardia, or tachycardia event. Once the breathing or heart rate returns to normal, the alarm stops. Each machine also keeps a log of any events, which is the term for when the alarm sounds, and records the pertinent data and vital signs. As an additional safety measure, CAS installed not only a back-up alarm, but also a feature that records whether the alarm sounded. This system operates primarily through an independent and separate microphone specifically designed to listen for the alarm. If it hears the alarm, it then makes a notation in the monitor's internal log. If it does not hear the alarm, then it records "Front alarm not heard," and the monitor will sound the backup alarm. A microphone listens for this back-up alarm as well and records whether it was heard. If the back-up alarm fails, all the lights on the front of the monitor flash.

Tragically, the child died from Sudden Infant Death Syndrome (SIDS), which essentially means that no attributable cause of death exists. Plaintiffs claimed the monitor's alarm never sounded that night. Additionally, they testified that all the lights on the front of the monitor were on, although they were solid and not flashing. Another family member who was asleep downstairs also allegedly could not recall hearing the alarm go off.  Plaintiffs further testified the machine was not turned off until the next day, when the monitor was removed for testing.

Plaintiffs filed a strict liability design defect claim against CAS, contending the monitor's software design caused the alarm to fail.  Their claim revolved around what is known as "spaghetti code," which is when computer code is unstructured and can result from the overuse of "goto" or "unconditional branch" statements, which causes a signal working its way through the code to jump around instead of following a linear path.  This in turn caused the signal to be pushed off course and never reach its destination.

To support this theory, the Graves designated three software experts to testify regarding the alarm's alleged failure. In arriving at their conclusions that a software defect caused the alarm to fail, none of the experts did much actual testing of the software. Instead, they used a "reasoning to the best inference" analysis, which was "similar to a differential diagnosis" in the medical field. In this case, three potential causes were identified: hardware error, complaint error, and software error. Complaint error means that the monitor was misused or the alarm did sound and the Graves failed to hear it.  All the experts were able to dismiss hardware error as a cause because the machine was tested and shown to be functioning properly. Thus, the question became whether complaint error or a software error occurred.

The experts excluded complaint error because the machine was hooked up properly, and they did not believe anyone would sleep through the alarm. In other words, because the Graves claimed the alarm did not wake them, that means it must not have gone off. After being confronted with the fact that the monitor listens for the alarm and separately records whether it was sounded, the experts opined that it must be "certain" the internal logs showing the alarm actually did sound were not reliable "in light of the undisputed testimony that the alarm did not function." That left software error as the most likely cause of the alleged failure, they opined.

Defendant moved to have all these experts excluded, arguing none of them met the reliability factors for scientific testimony set forth in State v. Council, 335 S.C. 1, 515 S.E.2d 508 (1999). CAS also moved for summary judgment, contending that without this expert testimony plaintiffs had no evidence of a design defect. The trial court agreed that their opinions were unreliable both as scientific evidence and as nonscientific evidence and thus were inadmissible. Having excluded the opinions of all the Graves' experts, the lower court granted CAS's motion for summary judgment.

The state Supreme Court noted that this was its first opportunity to assess the reliability of an opinion rendered using the "reasoning to the best inference" methodology, so looked for guidance to the analysis of the United States Court of Appeals for the Tenth Circuit, which had already done so. In Bitler v. A.O. Smith Corp., 400 F.3d 1227 (10th Cir. 2004), the court held that "[e]xperts must provide objective reasons for eliminating alternative causes" when engaging in this analysis. Id. at 1237. Furthermore, "an inference to the best explanation for the cause of an accident must eliminate other possible sources as highly improbable, and must demonstrate that the cause identified is highly probable." Id. at 1238. Although the expert need not categorically exclude all alternate causes, that does not relieve the expert of his burden to prove the alternate cause is at least highly improbable based on an objective analysis. See id. at 1237–38 & n.6. The court found this objectivity requirement consistent with the quality control element of State v. Council.

Here, there was evidence that the alarm worked properly and the plaintiffs failed to hear it. In addition to the monitor's recordation of hearing the alarm sound, the family pediatrician testified he believed plaintiffs slept through it, the court noted. The doctor was aware of just how exhausted the parents were. Although the alarm is loud, if one is tired enough, he testified that it is possible to sleep through it. His opinion was bolstered by the fact that the machine seems to have worked just as it was supposed to and recorded the breathing issues perfectly. The log also seems to show the alarm managed to stimulate the baby into breathing normally at times.

This evidence does not mean that is exactly what happened.  But there was enough that an expert needed to take it into account.. Instead, the experts simply assumed the alarm did not sound and provided no reason for discounting the evidence to the contrary other than the assertion of the persons alleging a failure. Thus, they did not objectively discount the evidence of complaint error as required. See Clark v. Takata Corp., 192 F.3d 750, 757 (7th Cir. 1999) ("Simply put, an expert does not assist the trier of fact in determining whether a product failed if he starts his analysis based upon the assumption that the product failed (the very question that he was called upon to resolve), and thus, the court's refusal to accept and give credence to [the expert's] opinion was proper.").

The trial court did not abuse its discretion in excluding the opinions, and summary judgment was warranted. 

Court of Appeals Reverses Daubert Decision

A tip of the hat to our DRI colleague Mike Weston for alerting us to an interesting 10th Circuit opinion from a couple weeks ago, Hoffman v. Ford Motor Co., 2012 WL 3518997 (10th Cir. Aug. 16, 2012).

Plaintiff was injured in a rollover car accident, and sued the car manufacturer alleging that a defect in the seat belt buckle caused it to release during the accident and allow her to be ejected from the vehicle.  In support of this theory, plaintiff presented the opinion of Dr. Good, a mechanical engineer, who theorized that the buckle most probably inertially unlatched during the accident due to an alleged design defect.  He ran a series of tests on buckles allegedly similar to the one in the accident, but ran into issues when he needed to make a comparison of the data from his lab tests to data from crash rollover tests to determine if the situation measured in the lab could actually occur in the real world.  Specifically, there was an absence of available data from relevant rollover crash tests (which present dynamic, multi-dimensional forces working on the component), and so he compared his results to data from planar crash data -- ones focused on only the horizontal plane (for example, a frontal car crash).

Ford moved to exclude the opinions as unreliable under Daubert, but the district court  (without a hearing) denied the motion, concluding Ford had failed to prove that the differences between the lab test results and the real world rollover accidents were significant.  Defendant appealed. (Note, whether she was even wearing her seat belt at all was hotly contested at trial. For purposes of the Daubert issue, the court assumed she was.) 

The court of appeals concluded that in permitting the testimony, the district court had not been "a sufficiently exacting gatekeeper; Daubert requires more precision."  Plaintiff failed to present a sufficient scientific connection between the accelerations and forces the expert found necessary to unlatch the buckles in the lab, and the acceleration and forces that would have occurred in the actual accident on the street. 

Specifically, the court of appeals held that the trial court should NOT have chastised the defendant for failing to show how the deficiency mattered, the failure to use rollover crash data. And the trial court should not have deemed it "unfair" for Ford to criticize the plaintiff because of the limited amount of rollover crash data available to the expert.  The state of the science is what it is.  And Ford did more than point out a deficiency in the method; it also explained why the deficiency rendered the testing and comparison suspect.  More importantly for our readers, "it was not Ford's burden to show Good's inertial unlatch opinion was unreliable and irrelevant.  Rather, it was plaintiff's burden to show reliability and relevancy."

It was undisputed engineering science that once a component is tested, the results must be applied to the whole vehicle setting; the lab results must be compared to data from the real world. Merely showing that similar buckles can be made to unlatch under certain lab conditions is irrelevant to whether the buckle at issue unlatched in the accident absent proof that the lab conditions were present and can be adequately and accurately related to the actual rollover-type accident.  Plaintiff's expert failed to explain adequately how the acceleration and forces present in the planar crash tests were similar enough to those present in a rollover accident. Nowhere did he show how his comparison was scientifically valid. Thus, his opinion was based on mere speculation, or on the assumption, that the levels of forces he found necessary to unlatch buckles in the lab were substantially similar to those that occurred in the subject accident.

Absent such evidence, plaintiff could not meet her burden.  Since plaintiff had a full and fair opportunity to present the case, and made no attempt to add or substitute other evidence, the court of appeals remanded with instruction for the district court to enter judgment as a matter of law for defendant.

 

 

Can Jury Ignore Uncontroverted Expert Opinion On Causation?

Here at MassTortDefense we often talk about the sufficiency of expert opinions, including on causation, from a legal Daubert or Frye standpoint.  A recent state court case from Texas reminds us about the rules on jury consideration of opinions that survive such legal challenges.

In Rentech Steel LLC v. Teel, No. 11-07-00318-CV (Tex. App., 11th Dist., 8/13/09), the plaintiff, who was working as a summer employee at Rentech's steel fabrication plant, suffered severe bilateral hand injuries while cleaning a power roller machine, a device that draws in steel plates and rolls them into cylinders. Rentech acknowledged some degree of fault but argued that some responsibility also rested with the settled manufacturer of the machine and the supplier.  The jury found Rentech negligent, but found no liability on the part of the other companies. Rentech appealed the finding of sole liability.

Expert William W.R. Purcell, a certified safety professional with degrees in civil and safety engineering and 40 years of experience, was retained by the plaintiff, but actually called by Rentech as an expert at trial.  He blamed the other defendants for inadequate warnings and instruction, and marketing defects, as well as agreeing there was negligence on the part of Rentech. Despite this uncontroverted expert testimony, the jury assigned liability only to Rentech.

The court of appeals noted that in Texas the jury is the sole judge of the witnesses’ credibility and the weight to give to their testimony.  Jurors may choose to believe one witness and disbelieve another and may disregard even uncontradicted and unimpeached testimony from disinterested witnesses.  Furthermore, even uncontroverted expert testimony does not bind the jury unless the subject matter is one for experts alone – one for which jurors “cannot properly be assumed to have or be able to form correct opinions of their own based upon evidence as a whole and aided by their own experience and knowledge of the subject of inquiry.”  Uniroyal Goodrich Tire Co. v. Martinez, 977 S.W.2d 328, 338 (Tex. 1998).

In this case, causation was not a matter for experts alone and did not require a technical or
scientific explanation, said the court;  it was within the jury’s ability to determine on its own what caused the accident and resulting injuries. See K-Mart Corp. v. Honeycutt, 24 S.W.3d 357, 361 (Tex. 2000)(holding that it was within jury’s ability to determine on its own whether lack of a railing caused the accident). Because causation was not an issue for experts alone, the jury could have disregarded Purcell’s conclusion as to causation.  The jury was free to conclude based upon the evidence presented at trial that Rentech failed to provide by a preponderance of the evidence (1) that the negligence of the other sellers was a cause of the accident and (2) that a marketing or design defect was a cause of the accident.

Other evidence before the jury included pictures of the actual roller machine and the warnings already located on the machine; testimony from a Rentech employee who operated the machine that a manual containing operating instructions had previously been supplied to Rentech; and testimony indicating that the Rentech employee operating the machine was knowingly violating the safety warnings and company policy at the time of the incident. Furthermore, the jury could have found that evidence proving a safer alternative design was lacking.