A minor fender bender in downtown Las Vegas involving a driverless shuttle and a human-driven truck shows that even when self-driving tech works as expected, accidents can still happen.

A few hours into its first day of service as part of a pilot program, the new shuttle carrying passengers Wednesday was stopped when hit by a delivery truck that backed into it. No one was injured.

The city released a statement that said the “shuttle did what it was supposed to do, in that its sensors registered the truck and the shuttle stopped to avoid the accident.”

City officials noted that if the human-driven truck had the same sensing equipment as the all-electric shuttle, it would have stopped and not grazed the shuttle's front fender.

The accident, while minor, illustrates the limits and potential dangers of autonomous technology as human-piloted and driverless vehicles begin to share the road, though still only in small doses.

The free shuttle even honked an automated horn that was triggered as the truck moved closer to it, said a representative from Keolis North America, which operates and maintains the shuttle for the city. There is a human driver present at all times on the shuttle, who can take manual control when needed, Keolis confirmed. 

William Wallace, an analyst with Consumers Union, the policy and mobilization division of Consumer Reports, said the driverless mishap demonstrates the need for greater transparency from companies developing the technology to understand what went wrong.

Consumers Union believes automakers and others developing autonomous car technology should be required to share more research data with the public and regulators to ensure the technology is reliable and vehicles safe enough.

"Consumer trust is going to be critical as these cars are developed," Wallace said. "To help bring about the promised safety and mobility benefits, and to avoid any backlash, companies would be wise to share detailed testing and validation data with regulators and the public showing how they know that self-driving cars are safe.”

A Long Way to Go

Jake Fisher, director of auto testing at Consumer Reports, said autonomous technology faces challenges in matching human capabilities behind the wheel.

“Will a car ever be able to be as good as a person? I don’t think so,” he said. “There are so many things we do without thinking about it.”

When human drivers are confronted with police directing traffic, for example, they can discern a wave summoning them forward from a hand telling them to stop, Fisher pointed out. 

The shuttle was taken out of service for a short time on Wednesday. A Keolis representative confirmed to Consumer Reports that it was back on its loop in the downtown Las Vegas Innovation District later that day.

The driver of the truck was cited by the Las Vegas Metropolitan Police Department, the city said.