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By Sanjay Adhia, M.D.

Multi-Plaintiff and Mass Tort Cases

The multi-plaintiff case is unique in civil litigation. I have served as an Expert Witness in several such cases which I discuss below. I find each plaintiff responds to an alleged event differently and must be assessed on a case by case basis. As a psychiatrist I am alert to psychological resiliency and psychiatric conditions that might be related to the case at hand.

Multi-plaintiff cases are not always class action lawsuits, though they can be. Contrary to popular belief, a multi-plaintiff case doesn’t always involve a public health disaster and a corporate defendant, though they can. Here are two very different types of multi-plaintiff cases on which I worked.

Two Cases

Chemical exposure is alleged to cause cancer with potential associated psychiatric illness. In this toxic tort, multiple plaintiffs claimed their risk of cancer was related to exposure to a chemical spill.

Multiple plaintiffs allege sexual assault. In this second case, 3 separate women accused a single defendant of serial sexual assault using “date rape drugs.”

People sue for Toxic Tort Chemical spill oil

Toxic Tort

This case involved a chemical exposure that may have caused late-onset cancers. I was retained by counsel for 2 of the 3 plaintiffs.

It was part of a BELO series (Back End Litigation Option). One plaintiff I examined developed anxiety symptoms from an ENT cancer.

After my Independent Medical Evaluation (IME) and review of records, I diagnosed one plaintiff with Anxiety Disorder Due to Another Medical Condition. 

This condition includes symptoms of intense anxiety or panic that are directly caused by a physical illness. Approximately 10% to 29% of Individuals with head and neck cancer experience symptoms of anxiety.[1] This diagnosis established a causal link between the chemical exposure and the anxiety if, in fact, the spill caused the cancer.

Consideration for the Mass Tort Attorney

If there are fewer than a dozen plaintiffs exhibiting symptoms, a highly qualified and efficient forensic psychiatrist can be an anchoring force in conducting IMEs and issuing opinions.

If there are many more plaintiffs, a group of experts can carry out the examinations more efficiently, and these specialists can work together cohesively.

Causation and Damages: The Medicine

In toxic torts, the opinions of toxicologists, neurologists, medical toxicologists and other experts are important to obtain the causal link and/or assess damages.

Forensic psychiatrists, as physicians, are better suited in cases involving medical issues than psychologists, who are not medical doctors. However, a neuropsychologist is qualified to conduct testing and the appropriate specialist if there is a concern exposure has led to cognitive problems. Multiple experts for Multiple Plaintiffs

It is not unusual for alleged toxic exposure to impact health. Various medical specialists may be involved.

Expert Witness Experienced in Mass Tort Cases

Retaining an expert with experience in mass torts can be helpful to the trier of fact. Mass torts have unique complexities and other nuances.

For example, if plaintiffs reflect a community, like a town or neighborhood, features of mental illness may present differently than if there is a single plaintiff and a single injury.

Case Merit, Damages Insight Early

Experience has led me to recommend that experts be retained earlier in the case to assist the law firm with triaging the plaintiffs who are most suited for IMEs. Read more.

[1]  https://www.mdpi.com/1718-7729/29/5/260/pdf?version=1651320225


multiple women allege their drinks were spiked before sexual assault.

Serial Sexual Assault

In this case, multiple women sued a defendant for emotional distress after sexual assaults. In this case, Drug Facilitated Sexual Assault (DFSA)* was a related factor. The plaintiffs were drinking and in at least one of the incidents, using an illicit drug. The plaintiffs reported similar scenarios: some time after the plaintiff had awoken, they realized they had been sexually assaulted.

The defendant was accused of adding a sedative medication to the respective plaintiff’s beverage, causing them to black out.

Defendant was convicted of DFSA and the three plaintiffs sued him in civil court.

In my capacity as a retained expert witness forensic psychiatrist, I examined one of the plaintiffs before the case was settled and issued my findings. In that case, the plaintiff developed anxiety, depression, and PTSD symptoms after the sexual assault. It affected her sporting career and caused significant emotional distress which impacted her career trajectory.

In cases involving intoxication and blackouts, it is important to retain a psychiatrist as opposed to a psychologist. The psychologist does not have the medical qualifications to discuss the psychopharmacology of DFSA, interpreting labs, and discussing blackouts.

I have been retained in several cases involving Drug Facilitated Sexual Assault. “Date Rape Drugs: Weaponized Chemistry” is my article on this site that dives deeper into this disturbing subject.

In DFSA cases, a Medical Review Officer (toxic screening/lab interpretation) can offer additional insight and testimony. I am an MRO and thus trained in interpreting drug testing and results. In early reporting of DFSA, the presence or absence of medications might be relevant. Learn more in What is a Medical Review Officer and MRO Certification?

Expert Witness Psychiatrist Houston

Multiple Medical Concerns

Multiple Plaintiffs

Multiple Evaluations

Evaluation by a Medical Expert Witness Team

Mass Tort and Toxic Tort cases are especially complex and symptoms usually indicate a need for medical-legal experts in complementary medical, psychiatric, or neuropsychological specializations. 

My work is in the realm of psychiatry, psychology and disciplines addressing cognitive and brain function. I collaborate with experts in these disciplines. I manage these moving parts so attorneys don’t have to.

A group of specialists working on a single case provides efficiency and a deeper understanding of findings, enabling evaluators to approach a question together.

This is a considerable benefit to attorneys as they need not find each specialist on their own, or guess about the area of expertise that is relevant.

For example, if a plaintiff claims their exposure caused cognitive decline, then a neuropsychologist is the right specialist to conduct tests on the parties. 

In another scenario, if a child or adolescent is a plaintiff, the forensic psychiatrist trained in Child & Adolescent Psychiatry may be asked to evaluate the young person. I work closely with Dr. Mendes for that reason given his training and qualifications.

Having one stop, saves time and gives the jury a more complete picture.