NEW YORK (Reuters) - As the U.S. Congress moves quickly to pass the first federal law governing self-driving cars, some state and city officials are pushing back over fears that the measure will limit their ability to regulate vehicle safety at the local level.

FILE PHOTO: A self-driving car being developed by nuTonomy, a company creating software for autonomous vehicles, is guided down a street near their offices in Boston, Massachusetts, U.S., June 2, 2017. REUTERS/Brian Snyder/File Photo

The debate highlights the challenges of rolling out a new technology that does not fit neatly into an existing regulatory framework. States traditionally regulate the driver while the federal government regulates the car, but that division of labor may be hard to maintain when cars have no drivers.

Industry officials say a single, nationwide set of standards would speed the development of self-driving vehicle technology, ultimately lead to fewer highway deaths, and keep the United States in the forefront of automotive technology.

The U.S. House of Representatives unanimously approved the sweeping bill last week, and U.S. Senator John Thune said on Wednesday he wanted to move the bill out of committee by early October.

The federal bill bars states and cities from implementing “unreasonable restrictions” on the rollout of self-driving cars. Critics say the vague language could lead the industry to sue states over any regulations they consider overly burdensome.

“If Congress preempts state and local governments from enacting smart safety protections, the adoption of this amazing technology could be unnecessarily delayed by court challenges and state legislative action,” said Leah Treat, director of the transportation bureau in Portland, Oregon, which is set to enact its own self-driving regulations by the end of the year.

In a Sept. 5 letter to U.S. congressional leaders, the National Governors Association, the National Conference of State Legislators and other groups said the federal rules encroached on state authority and urged federal lawmakers to change the bill’s language.

The new measure authorizes manufacturers to put 25,000 self-driving cars on the road in the next year for testing. Those numbers would gradually increase, with a total of 275,000 vehicles permitted by 2021.

Critics of the federal bill said they generally support the development of self-driving technology but felt neglected and overruled by federal legislators.

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“California, for example, has higher emission standards,” said Jennifer Cohen, government affairs director for the Los Angeles Department of Transportation. “Does the federal preemption preclude us from enforcing these? Can we still protect our school zones?”

FEDERAL VS. STATE

Though fully-autonomous cars are still years away from widespread adoption, 25 states have already passed legislation or issued executive orders related to autonomous vehicles, according to the National Conference of State Legislators.

New York, for example, has taken a strict approach to testing, requiring self-driving cars to follow an approved route with a police escort. The state also has a law that requires drivers to have at least one hand on the wheel of any car, though it was suspended until April 2018 to accommodate autonomous vehicle testing.

Data-sharing is also a major flashpoint. Pittsburgh Mayor Bill Peduto said earlier this year he was disappointed Uber, which is testing a fleet of autonomous vehicles there, has been hesitant to share data the city could use to improve traffic flow and infrastructure.

Uber said it would share some data starting this year on a voluntary basis, but Chan Lieu, a former director of governmental affairs at NHTSA who is now an advisor to the Self-Driving Coalition for Safer Streets, which includes Ford, Alphabet’s Waymo, Volvo Cars, Uber [UBER.UL] and Lyft, said the companies would oppose broad data disclosure requirements.

There are privacy concerns, he said, as well as commercial fears of revealing trade secrets.

California currently requires the industry to hand over data on vehicle disengagements and collisions, and the National Association of City Transportation Officials has called for the federal government to adopt similar requirements.

Not all states are concerned about the federal bill. Arizona governor Douglas Ducey issued a 2015 executive order saying his state supported the self-driving industry and hoped the technology would bring new jobs to the state.

Arizona does not currently impose any restrictions on self-driving cars. Kevin Biesty, the deputy director for policy at Arizona’s department for transportation, said the state largely trusted automakers to adapt their technology as concerns arise.

“One of the reasons we did not step forward and regulate is because the industry is changing so fast and what you release today might become obsolete in six months,” he said.