According to the Nevada Legislature's website, AB 511 "revis[ing] certain provisions governing transportation" passed the Assembly (36-6) and the Senate (20-1) and was signed into law by the governor this week. Although I am aware of no law that prohibits driverless cars, this appears to be the first law officially to sanction the technology. Specifically, the law provides that the Nevada Department of Motor Vehicles "shall adopt regulations authorizing the operation of autonomous vehicles on highways within the State of Nevada." The law charges the Nevada DMV with setting safety and performance standards and requires it to designate areas where driverless cars may be tested. (Note that this could take some serious time: Japan, for instance, has been promising standards for personal robots for years and has yet to release them.)
I believe a previous version of the bill had an exception to the ban on texting for passengers in cars that drove themselves. Otherwise, the law is substantially similar to the bill I discussed in April. So I have the same nits. Overall, however, this is great development. Autonomous driving has serious potential but its safety and savings need to be evidenced in a controlled environment. Nevada---former host of the DARPA Grand Challenge---is now the lead car in the caravan. PDF of the law is attached below. UPDATE: The texting ban exception was passed as a separate bill. It reads in relevant part: "For the purposes of this section, a person shall be deemed not to be operating a motor vehicle if the motor vehicle is driven autonomously through the use of artificial-intelligence software and the autonomous operation of the motor vehicle is authorized by law." Thanks Bryant!