There's little doubt that the technology for autonomous cars already exists, but the implications of its real-world use are less clear. After all, in most countries it's not clear whether ceding complete control of a vehicle to a machine is even legal.

The situation may become less ambiguous thanks an amendment to the United Nations Convention on Road Traffic proposed last month, which would let drivers take their hands off the wheel in a self-driving car, Reuters reports.

Pushed by France, Germany, and Italy, the new rule allows cars to drive themselves on public roads, as long as a human driver is present and there is a way to switch back to manual control. It would alter Article 8 of the 1968 Convention on Road Traffic, which states that "every driver shall at all times be able to control his vehicle or guide his animals."

The amendment comes as several European carmakers undertake large-scale autonomous-car research projects. Mercedes-Benz demonstrated a fully-autonomous S-Class last fall, while Volkswagen and other companies are collaborating on the technology in VW's hometown of Wolfsburg, Germany. Volvo is also testing self-driving cars on public roads in Sweden and Nissan has promised to launch an autonomous car on the market by 2020.

If the amendment passes, all 72 countries that are party to the convention would have to work the new rule into their laws. Those countries include European nations, Mexico, Chile, Brazil, and Russia, but not the United States, China, or Japan.

So far, the legal status of self-driving cars in the U.S. has been ambiguous. Nevada passed a law legalizing testing of self-driving cars in 2011, followed by California, Florida, and Michigan. However, Google had been testing its self-driving cars on California roads before any of these laws passed.


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