drug test negligenceFor cases involving science, such as addressing the accuracy of an employer’s drug test, it’s important to have a medical or forensic science expert witness to bring insight and clarity.

An employee appealed the district court’s dismissal of his negligence action arising from a failed drug test administered by Defendant Drug Testing Company based on the opinion of a medical expert that causation had not been diligently investigated.

Plaintiff worked for a Louisiana Refining Company that selected him for a random drug test. Defendant’s employee collected a chest hair from Plaintiff for testing by an independent laboratory. The lab reported to Defendant that Plaintiff’s hair tested positive for the metabolite of THC in marijuana. Defendant’s medical review officer told Plaintiff about the test results and asked Plaintiff only if he used marijuana. Plaintiff said no, but she allegedly didn’t ask any further questions. Refining Company fired Plaintiff for the failed drug test. Plaintiff filed suit against Defendant, lab, and the medical review officer for negligence, and only the claim against Defendant was the subject of the appeal.

The district court granted Defendant’s motion for summary judgment, holding that Plaintiff failed to adequately identify the duty owed by Defendant to him, and that there was no genuine dispute of material fact as to causation.

On appeal, Plaintiff contended the district court erred in holding that the evidence didn’t create a genuine dispute of material fact as to causation. The Fifth Circuit Court of Appeals, in a Per Curiam decision, wrote that it would assume (without deciding) that Defendant owed Plaintiff a duty to investigate whether his positive test result was a false positive in order to examine the sufficiency of the causation evidence.

Plaintiff provided and referenced only two pieces of evidence: the medical records of his doctor and the declaration of his medical expert, whose short declaration stated that Versed is a sedative that Plaintiff was administered for issues with his joints. Versed is a chemical that can be hydrolyzed to give a hydrolysis product that has a mass of 344 amu—the same mass as the THC metabolite that’s the basis of a positive test for THC when tested. So it was possible that the metabolite of Versed was the actual compound that in the hair sample that was tested for the presence of the THC metabolite from marijuana use and that no THC was in the sample. The false-positive would have been produced from the presence of the Versed.

Plaintiff’s argument that Defendant breached its duty to investigate caused his termination was dependent on at least three premises: had Defendant investigated the positive test result, Defendant would have discovered that Plaintiff had ingested Versed; the hair collected from Plaintiff contained Versed; and Versed was mistaken for THC.

The medical records showed that Plaintiff was administered Versed intravenously prior to a medical procedure a few months earlier. Therefore, the Court assumed Defendant would have discovered this fact had it investigated. However, there was insufficient evidence to create a genuine dispute that the hair contained Versed. Although Plaintiff’s medical expert’s declaration seems to be based on the assumption that the hair contained Versed because of prior ingestion, he didn’t specifically claim the hair contained Versed. Nor did the expert give an explanation as to how the hair could have contained Versed.

Plaintiff ingested Versed seven months before the test. One of Defendant’s experts opined that the test results demonstrated Plaintiff used marijuana on several occasions during that period. But the court ruled that this expert’s opinion about the length of time didn’t address Versed, was limited to marijuana only, and was never extrapolated to other drugs. There was no evidentiary basis presented for assuming that the hair could have contained Versed ingested seven months prior just because the hair contained marijuana ingested seven months prior. Plaintiff claimed the medical records showed that Versed was administered to him, but there was insufficient evidence that the hair could have contained Versed ingested in December 2013.

Even if there was evidence that the hair contained Versed, the Court of Appeals agreed with the trial court which held there was insufficient evidence to create a genuine dispute that Versed was mistaken for the metabolite of THC in marijuana. A reasonable jury couldn’t find for Plaintiff based on his expert’s declaration, and as a result, there was no genuine dispute concerning whether Versed could cause a false positive. Plaintiff’s expert’s opinion was speculative, conclusory, and lacked a reasonable basis.

Unsupported expert affidavits setting forth ultimate or conclusory facts and conclusions of law are insufficient to either support or defeat a motion for summary judgment, the Court said. Without more than credentials and a subjective opinion, an expert’s testimony that “it is so'” doesn’t suffice to preclude summary judgment. Testimony based on conjecture or speculation is insufficient. The Fifth Circuit noted that it has repeatedly held that a “single conclusory expert affidavit, devoid of any factual support or explanation of the expert’s basis” for his or her conclusion, is “insufficient to meet [a] [p]laintiff[‘s] burden of ‘designat[ing] specific facts showing that there is a genuine issue for trial.'”

In summary, Plaintiff’s medical expert opined it was “possible” that Versed was mistaken for the THC metabolite or Versed “would have” been mistaken for the THC metabolite “when tested…” because “hydrolyzed” Versed and the THC metabolite have the “same mass.” But he didn’t explain how the Versed that Plaintiff ingested hydrolyzed. The expert seems to assume, the Court reasoned, that the Versed hydrolyzed then entirely relied on the similar mass of hydrolyzed Versed and the THC metabolite to support his conclusion. In doing so, he implied the THC metabolite is identified in a test by mass, but he didn’t clearly explain whether the THC metabolite was identified by mass, or more importantly, whether mass was the only identifier. In contrast, Defendant’s experts testified that Plaintiff’s medical expert’s testimony on the mass was “scientifically incoherent.” The mass of a Versed metabolite was irrelevant to the presence of the carboxy-THC metabolite found. The weight of one metabolite doesn’t mean that it could manifest as a different metabolite. In addition, Plaintiff’s medical expert only referred to the test, while Defendant’s experts explained that three separate tests were performed on different portions of Plaintiff’s hair—all of which reported positive for the presence of the THC metabolite above an established limit.

As a result, the Court found that Plaintiff didn’t offer any evidence that the test was a false positive. As to the tests, Plaintiff’s expert stated it was “possible” that Versed was mistaken for the THC metabolite or Versed “would have” been mistaken for the THC metabolite. The statements were tentative, the Fifth Circuit held. However, all three of Defendant’s experts opined or concurred that the presence of the THC metabolite could only have been caused by the ingestion of marijuana. Plaintiff’s expert’s declaration set forth conclusions that were devoid of any factual support or explanation beyond mere speculation. Accordingly, neither Plaintiff’s medical expert’s declaration, nor the fact Plaintiff ingested Versed, created a genuine dispute that a breach of a duty to investigate caused his termination.

The Fifth Circuit found no genuine dispute as to the causation element of Plaintiff’s negligence claim. Accordingly, the district court did not err in granting summary judgment in favor of Defendant, and the judgment was affirmed.