At a signing ceremony at the Google headquarters on Tuesday, California Governor Jerry Brown signed into law state legislation that officially makes the Golden State the second in the nation to legalize and regulate autonomous cars.

Google, of course, has already developed a fleet of a dozen cars (mostly modified Toyota Priuses) and has already logged over 300,000 miles of autonomous driving on state roads.

The new law obliges the California Department of Motor Vehicles to draft regulations for autonomous vehicles by January 1, 2015.

"These vehicles have the potential to avoid accidents—we can save lives, create jobs, and reduce congestion," said Google co-founder Sergey Brin at the event. "I expect that self-driving cars will be far safer than human-driven cars."

Nevada became the first state earlier this year to regulate autonomous cars, and the Los Angeles Times reports that Arizona, Hawaii, Florida, and Oklahoma are considering autonomous-vehicle legislation.

For now though, scholars say that Google will need to log a more significant number of hours to prove that these cars crash less often than normal cars.

"Google's cars would need to drive themselves (by themselves) more than 725,000 representative miles without incident for us to say with 99 percent confidence that they crash less frequently than conventional cars," wrote Bryant Walker Smith, a Stanford Law fellow who is teaching a class on autonomous vehicles this fall, in a blog post earlier this year.

"If we look only at fatal crashes, this minimum skyrockets to 300 million miles," he added. “"To my knowledge, Google has yet to reach these milestones."