The National Park Service's duties in overseeing concessions at Yosemite National Park are discretionary and so the agency should not be held liable for a hantavirus outbreak there in 2012 that killed three and sickened others, the federal government argues in a motion to dismiss the agency from the litigation.

As the concession at Curry Village where the outbreak occurred is managed and operated by DNC-Yosemite employees, the Park Service can't be held liable for their actions as those "employees are independent contractor employees, not government employees," the attorneys state.

Ten park visitors were infected by the rodent-carried disease, which produces flu-like symptoms and can lead to fatal respiratory complications, and three died from it.

In an interview with the Traveler in 2012, Dr. Danielle Buttke, an epidemiologist for the National Park Service who investigated the outbreak, said the most common way for the disease to spread from a rodent to a human "is to have a mouse urinate in an area, and if it is an infected mouse the virus is spread in the urine and then that urine can be stirred up in dust, and a person would inhale that virus in the dust that’s stirred up. That’s the most common route of infection."

The outbreak led to the discovery of deer mice nesting within the double-walled Signature Tent Cabins. It would, in theory, be possible for urine-contaminated dust from those nests to migrate into the cabin's interior, she said.

Five lawsuits arose in the wake of the outbreak, and in September they were consolidated into one master complaint that included nine charges against the federal government: wrongful death, survival, negligence, premises liability, loss of consortium, breach of warranty, failure to warn, negligent infliction of emotional distress, and civil conspiracy.

While the government can be sued under the Federal Tort Claims Act, that Act contains exceptions that leave the government's sovereign immunity intact. In the motion for dismissal, which is scheduled to be heard March 27, 2015, the government argues the Act contains a "discretionary function exception" that would leave the sovereign immunity in place in the case at hand. More so, the Act's "waiver of sovereign immunity is limited to the acts and omissions of agents or employees of the United States," and the hantavirus outbreak arose in tent cabins overseen by DNC-Yosemite employees, the motion states.

To buttress its position, the government cited a section of the National Park Service's Management Policies that states, "These management policies do not impose park-specific visitor safety prescriptions. The means by which public safety concerns are to be addressed is left to the discretion of superintendents and other decision-makers at the park level who must work within the limits of funding and staffing. Examples include decisions about whether to install warning signs . . . [or] eliminate potentially dangerous animals . . . ."

Beyond that, the motion goes on, the Park Service relies "on the expertise of private concessioners to provide visitor services, given the limitations that the NPS had in its ability to do so itself..."

And, the lawyers argue a bit later, "the (Supreme) Court has ruled that the United States is not liable for the actions of a contractor, even when the contractor receives federal money and must comply with federal regulations, as long as United States employees do not engage in substantial supervision of the day-to-day operations of the contractor."

"...With respect to the claims in this case, it is clear that DNC-Yosemite employees, not NPS employees, supervised and performed the detailed physical work of operating and maintaining the tent-cabins at Curry Village. The concessions contract generally describes the operations and maintenance responsibilities of DNC-Yosemite and leaves the details of implementation to DNC-Yosemite," they wrote.

Overall, the government maintains, there are many risks in national parks that the Park Service must manage, and it does so with the discretion and resources it has been given.

...in managing the Hantavirus risk and other natural risks at Yosemite, the NPS not only considers the type of risk in comparison with other risks in the park, but also how managing the risk might impact Yosemite’s natural, historical, and cultural resources as well as its ability to provide a low-impact and rustic lodging alternative for visitors. The actions that the NPS takes to manage risks at Yosemite are also necessarily constrained by limitations on its budget and staffing. Allowing courts to second-guess how a national park manages such natural risks would upset the ability of the NPS to balance important policies that allow it to provide public use of the national parks while conserving their resources.