As reported last week, California State Governor Jerry Brown duly signed legislation to establish safety and performance regulations to test and operate autonomous vehicles on roads across the state.
The bill was signed at the headquarters of Google, which has been testing autonomous computer-controlled vehicles for several years.
The bill requires the California Department of Motor Vehicles to draft the regulations by 2015.
A licensed driver would still be required to sit behind the wheel, however, to provide back-up in an emergency.
Google has said that it has logged more than 300,000 miles in its fleet of 12 cars without an accident - although one of its vehicles was involved in a minor crash in summer 2011. The company said it was being driven manually at the time.
Google co-founder Sergey Brin said self-driving cars would be "far safer" than those driven by humans, adding that he thought the vehicles would be commercially available within the decade. He also argued that autonomous vehicles could make better use of the road and reduce the size of car parks by fitting into smaller spaces than humans could get them into.
The cars are powered and controlled using a combination of sensors, location tracking and on-board computing to drive the vehicle safely.
The latest statistics on road traffic accidents in the UK figures over 60% of fatalities in reported road accidents had driver or rider error or reaction.
Long term economic prognosis
The Observer columnist John Naughton provocatively suggests Google's self-guided car could drive the next wave of unemployment as they make human skills worthless.
Advances in computing of the kind embodied by the Google self-driving car represent the next wave of job-eliminating technology. Its engineers have demonstrated that with smart software and an array of sensors, a machine can perform a task of sophistication and complexity most of us assumed would always require the capabilities of humans. And that means our assumptions about what machines can and cannot do are urgently in need of updating.