Safety advocates say the additional guidelines still fall short.
The Department of Transportation "continues to insist that eliminating regulation is the way to achieve safety," said Jason Levine, executive director of the Center for Auto Safety.
"Despite cybersecurity vulnerabilities continuing to dominate headlines, and rising public concern surrounding driverless cars, NHTSA is still failing to require the submission of any information about the most basic level of safety prior to this technology being deployed on our streets and in our neighborhoods."