California regulators have released a new proposal to allow the testing of self-driving heavy-duty trucks on public roads.

The state’s department of motor vehicles announced proposed regulations on Friday to allow the testing of driverless trucks over 10,001lbs, opening the door for companies to test self-driving technology on vehicles roughly the size of a Ram or Ford super duty pickup truck.

Regulators say self-driving heavy-duty trucks are already being tested in other states including Texas, Arizona and Arkansas. California is the only state with regulations that explicitly ban them.

The proposed regulations, which were posted online, are subject to a public comment period that ends in June.

They will likely face pushback from safety advocates and the labor unions that represent the state’s hundreds of thousands of commercial truck drivers, who are concerned about losing truck-driving jobs to automation in the future.

The California legislature passed a bill in 2023 to require human drivers aboard self-driving semi-trailer trucks, but it was vetoed by governor Gavin Newsom, who said additional regulation was unnecessary because existing laws governing self-driving vehicles were sufficient. The Teamsters union lobbied heavily for the bill.

California currently prohibits any type of autonomous vehicle that weighs more than 10,000lbs on public roads.

The proposed regulations for heavy-duty trucks aim to enhance data-reporting requirements for manufacturers, such as reporting instances when cars stop in the middle of an active road for any reason and need to be retrieved. They will give the state’s DMV more authority to apply “incremental enforcement measures” against companies instead of fully suspending their testing permits.

The DMV suspended the permit of driverless car company Cruise in 2023 after one of the company’s self-driving cars struck a pedestrian in San Francisco. The pedestrian sustained life-threatening injuries.

Research has shown that vehicles with higher front ends, like heavy-duty pickup trucks, are more likely to cause fatalities in collisions with pedestrians.