The U.S. Department of Transportation (DOT) and the National Science and Technology Council released an update to the DOT's policy regarding autonomous vehicles on 8 January 2020. The document, "Ensuring American Leadership in Automated Vehicle Technologies: Automated Vehicles 4.0" (AV 4.0), follows two previous Trump administration policy statements from the DOT regarding its approach to autonomous vehicles: "Automated Driving Systems 2.0: A Vision for Safety" (ADS 2.0) released in September 2017 and "Preparing for the Future of Transportation: Automated Vehicles 3.0" (AV 3.0) released in October 2018. Secretary of Transportation Elaine Chao unveiled the new guidelines in her keynote speech at the Consumer Electronics Show conference in Las Vegas, Nevada.