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What legal responsibility, if any, does a Massachusetts business have to prevent the spread of COVID-19 to its employees and customers?

It’s too early to tell.

Nevertheless, at least one legal doctrine should be considered.   And that’s the “Eggshell Plaintiff Rule.”

The rule states that a defendant is liable for all harm that “naturally flows” from the defendant’s negligent actions.

This applies even when the harm to a plaintiff is made much worse by his or her preexisting medical condition.

The rule was defined by the Massachusetts Supreme Judicial Court in Wallace v. Ludwig, 292 Mass. 251 (1935):

where an injury arising from a cause which entails liability on the defendant combines with a preexisting or a subsequently acquired disease to bring about greater harm to the plaintiff than would have resulted from the injury alone, the defendant may be liable for all the consequences. If the injury causes or contributes to cause the development of a preexisting disease, the person liable for the injury is liable also for the resulting aggravation. The wrongdoer may be held responsible for the harmful results of the combined effects of his or her wrongful act and the disease. . . . If the injury directly causes disease, even though it was not theretofore present in the system of the person injured, liability of the wrongdoer extends to all injurious results of such disease.

This rule could have a big impact on future cases involving patrons or employees who are exposed to COVID-19 due to a business’s “negligent” conduct.

COVID-19 data (for what it’s worth) indicates that the virus has the greatest impact on those with preexisting medical problems.

For instance, here in Massachusetts, 98.3% of the 6,473 COVID-related deaths involved people with underlying medical conditions.

(These numbers are from the Massachusetts Board of Public Health’s COVID-19 Dashboard last updated on May 26, 2020.)

Furthermore, according to the Centers for Disease Control and Prevention, the fatality rate for those infected with the virus could be as low as 0.25%.  (See Case-Fatality Risk Estimates for COVID-19 Calculated by Using a Lag Time for Fatality.)

Despite the virus’s low risk to the general public, it seems likely that, based on the eggshell plaintiff rule, a plaintiff with underlying medical problems who contracts COVID-19 as a result of a business’s “negligence” may have a legal claim for any harm that results from the infection.

This matter will likely be determined by future court rules or state legislation.

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