Briana Leakas v. Monterey Bay Military Housing, LLC

Background

Briana Leakas, her minor son D.L., and Theodore Leakas, Ms. Leakas’s spouse and D.L.’s guardian ad litem, brought claims for personal injuries allegedly caused by toxic mold contamination in a home they leased from defendants while living at the U.S. Army Garrison Presidio of Monterey from about June 2019 through May 2020. The operative amended complaint asserted ten state and common-law claims, including negligence, nuisance, negligent misrepresentation, negligent infliction of emotional distress, breach of the implied warranty of habitability, breach of the implied covenant of quiet use and enjoyment, gross negligence, premises liability, constructive eviction, and fraud by concealment.

The defendants moved to exclude testimony from plaintiffs’ retained medical expert, David Ross, M.D., a board-certified neuropsychiatrist. Based on his examination of Ms. Leakas, medical records, and other materials, Dr. Ross concluded that mold exposure caused an acquired brain injury associated with Chronic Inflammatory Response Syndrome, or CIRS. Defendants argued that Dr. Ross was not qualified to address medical issues outside neuropsychiatry and that his causation opinion was not based on sufficiently reliable medical testing or data.

Legal standard

Under Federal Rule of Evidence 702, expert testimony is admissible only if the expert is qualified, the testimony will help the factfinder, the opinion rests on sufficient facts or data, the methods are reliable, and the expert reliably applied those methods to the facts. The party offering the expert testimony bears the burden of showing that it is more likely than not admissible. The court applied its role as the gatekeeper of expert evidence under Rule 702 and the principles governing relevance and reliability.

Qualifications

The court found that Dr. Ross’s qualifications permitted him to testify that, based on his evaluation, Ms. Leakas had brain abnormalities. He could also testify about whether and to what extent those abnormalities were consistent with neuropsychiatric symptoms or conditions he had observed in treating patients with mold-related brain injuries.

The court found that plaintiffs had not shown that Dr. Ross was qualified to testify about medical issues beyond neuropsychiatric symptoms or conditions, including impairments involving other bodily systems. The court also found that he was not qualified to testify about Ms. Leakas’s long-term-care or life-care-planning needs.

CIRS and causation opinion

The court ruled that Dr. Ross could not testify or suggest that the CIRS diagnosis was his own. His report showed that he relied on a CIRS diagnosis reportedly made by Ms. Leakas’s treating providers and on diagnostic criteria from another retained expert. The court also concluded that plaintiffs had not shown that CIRS was sufficiently accepted as a diagnosis for Dr. Ross’s proposed testimony to satisfy Rule 702 on the record presented.

The court separately examined Dr. Ross’s differential diagnosis, which is a method of identifying the most likely cause of a medical condition by considering and eliminating potential causes. The court found that his analysis was circular: he assumed that Ms. Leakas had CIRS caused by mold exposure based on other people’s diagnoses and then concluded that his tests and analyses were consistent with that diagnosis. The court held that plaintiffs had not shown that his method reliably linked Ms. Leakas’s brain abnormalities to mold exposure from years earlier.

The court permitted Dr. Ross to testify about his testing and analysis of Ms. Leakas’s brain, including his use of NeuroQuant® and NeuroGage®, and about what that testing showed concerning her neuropsychiatric symptoms and conditions. But the court emphasized that those programs were not diagnostic tools for CIRS, mold exposure, or mold-related illness and were not cleared by the Food and Drug Administration for those purposes. Dr. Ross therefore could not testify that his analysis showed that mold-related CIRS caused Ms. Leakas’s brain abnormalities. The court stated that some challenges to the testing could be explored through cross-examination, but the causation opinion itself was inadmissible.

Disposition

The court granted in part and denied in part defendants’ motion to exclude Dr. Ross’s testimony. Dr. Ross may not testify that Ms. Leakas has an acquired brain injury caused by CIRS due to mold exposure, and he may not testify about her long-term-care or life-care-planning needs. He may otherwise testify to a limited extent consistent with the court’s rulings.