On-demand car service Uber is facing a new wrongful death lawsuit following the tragic death of a 6-year-old girl on New Year’s Eve.

According to a lawsuit filed on Monday, Uber is guilty of negligence in the wrongful death of Sofia Liu.

On December 31st at around 8pm, Liu was walking down Polk Street in San Francisco with her brother Anthony and mother, Huan Kuang. The suit alleges that as they all attempted to cross at the intersection of Polk and Ellis, they were struck by a car driven by Uber employee Syed Muzzafar.

The accident took the life of Sofia and “caused serious and significant physical and mental injuries” to Huan and Anthony.

Uber quickly acknowledged the accident, but made it clear that the driver (Muzzafar) was not actually providing services for Uber at the time of the accident. Here’s what the company had to say on New Year’s Day:

Our hearts go out to the family and victims of the tragic accident that occurred in downtown San Francisco on New Year’s Eve. We extend our deepest condolences.

We work with transportation providers across the Bay Area. The driver in question was not providing services on the Uber system during the time of the accident. The driver was a partner of Uber and his account was immediately deactivated.

We are committed to improving the already best in class safety and accountability of the Uber platform, for both riders and drivers.

But according to the Plaintiffs, this distinction is irrelevant.

The lawsuit was first reported by the New York Times. The family’s argument against Uber basically has two prongs – one challenging the notion of what it means to really be “on the clock” while employed at Uber and another taking issue with Uber’s app, how it relates to the company’s entire business premise, and how it could run afoul of California law.

From the NYT:

Uber asserts that Uber drivers without fares are not Uber cars. The suit, filed by Chris Dolan, a San Francisco lawyer, directly challenges this effort by the company to detach itself from its own users. It says Uber needs the vehicles to be logged into the Uber app — that’s the only way potential riders know there is a car in the vicinity. So even when there is no fare in the car, the drivers are in essence on the clock, working for Uber.

When drivers accept a call, furthermore, they need to interface with the app. The suit goes on to note that under California law, it is illegal to use a “wireless telephone” while driving unless it is specifically configured to be hands-free — which the app is not. In essence, the suit argues that Uber was negligent in the “development, implementation and use of the app” so as to cause the driver to be distracted and inattentive.

Of course, any future ruling in this case carries implications for all ride-service companies.

Uber, founded in 2009, says that they “seamlessly connect riders to drivers through our app, make cities more accessible, [and] open up more possibilities for riders and more business for drivers.” Uber currently operates in over 50 cities in more than 20 different countries.

Image via Uber, Facebook