The safety practices of ride-hailing service Uber are receiving increased attention after 45-year-old Uber driver Jason Dalton allegedly went on a deadly shooting spree in Kalamazoo, Michigan.
Uber's screening service is coming into question, although Dalton had no record of criminal history and his background didn't show anything unusual, authorities said.
Investigators said Dalton killed six people and wounded two others in a random shooting rampage last weekend. Authorities said he shot his victims in between driving passengers for Uber.
Though the driver passed Uber's prescreening process, Uber's five-star rating system provides an additional level of scrutiny that allows passengers to assess their driver's behavior. When passengers are matched with a driver, they are able to see this rating along with the driver's name, license plate number and photo.
"None of the things that we did do in this case, if we made them somehow better, would have made any difference," Uber chief security officer Joe Sullivan told reporters Monday. "There were no red flags, if you will, that we could anticipate things like this."
Dalton's rating by customers was "good" before the killings, with a 4.73 out of 5 stars, according to Sullivan. He had not received many complaints from passengers until Saturday, when several passengers made note of his erratic behavior.
One passenger wrote on Facebook to warn others in the area that the driver had "sideswiped a car blowing through the stop sign at Henderson castle and West Main Hill, and the driver continued driving."
While Uber does not explicitly lay out this policy, a passenger can cancel a request for a ride with a driver who has less than 5 stars if it is made five minutes after the request. After five minutes, passengers will incur a cancellation fee of about $10 — the price varies slightly by location — to compensate the driver for his or her time. On uberPOOL trips, where passengers share a ride and split the cost, riders may be charged a fee if they cancel their ride after getting matched with a driver no matter the time frame.
Uber in the United States did not provide an outline on how drivers receive their current number of stars, but Uber's Melbourne site notes that drivers should aim to receive 4.6 stars or more. Uber can ask a driver to come into the office so they can receive "tailored feedback" if their rating falls below the average, which varies by location.
When a driver's rating is consistently below average, drivers may lose access to the Uber Partner app. Passengers are also prompted to provide specific feedback about a range of options regarding their ride, such as the state of the car's cleanliness, the driver's attitude and professionalism, and the efficiency of the driver's route choice.
Actions listed as unacceptable on the Uber platform include inappropriate behavior, contacting a rider, accepting cash, driving in the wrong vehicle and calling a rider for a destination.
Despite these features, Uber officials stressed during the conference call that Dalton's track record did not exhibit any warning signs.
Ed Davis, a former Boston police commissioner who sits on Uber's safety advisory board, said, "A background check is just that — it does not foresee the future."
— CNBC's Dan Mangan contributed to this report.