Michigan would no longer require that someone be inside a self-driving car while testing it on public roads under bills advancing in the Legislature.
The change won unanimous Senate approval Wednesday and could reach Gov. Rick Snyder's desk within months.
The legislation is designed to keep the auto industry's home state ahead of the curve on autonomous vehicles.
A researcher wouldn't have to be present in a self-driving test car.
But the researcher would be required to "promptly" take control of its movements if necessary, or the vehicle would have to be able to stop or slow on its own.
The bills also would authorize the public operation of driverless cars and tight "platoons" of trucks to travel in unison at electronically coordinated speeds.
Editor's note: This story has been updated to add the Senate vote.