The U.S. Transportation Department's updated self-driving vehicle development guidelines released Thursday continue the Trump administration's focus on making sure regulations are not "barriers" to innovation.

That approach, panned by some safety advocates as borderline negligent, means the government will continue to rely on industry to police itself as companies pour billions of dollars into self-driving research and development. The new guidelines build upon previous efforts, such as a version issued during a visit last year by Transportation Secretary Elaine Chao to Ann Arbor.

In explaining the reasoning behind the hands-off approach, Chao said that voluntary compliance and self-reporting are what boost safety, not fear of punishment, and she said the government should not be a hindrance to developing technology.

"This (Transportation) department is not in the business of picking winners and losers. … Consumers and users will ultimately decide which technology or package of (technologies) suits them best,” Chao said.

The new guidelines, called "Preparing for the Future of Transportation: Automated Vehicles 3.0," tout six principles, including prioritizing safety, remaining technology neutral, modernizing regulations and encouraging a consistent regulatory and operational environment.

Here are a few highlights from the 80-page report:

Guidelines are voluntary, rather than being regulations, which "could stifle innovation."

10 sites across the country designated by the department as automated vehicle proving grounds in 2017 will lose that distinction.

The department may set safety standard exceptions for automated driving system-equipped vehicles "that are relevant only when human drivers are present." That could allow for the removal of features such as steering wheels, something General Motors has requested.

A study will be conducted on the workforce impacts of automated vehicles.

Regulators will propose streamlining the process for getting exemptions to the federal safety standards. The "proposed changes will remove unnecessary delays in seeking public comments ..."

Regulations will no longer assume that a commercial motor vehicle driver is always a human or that a human is necessarily present during operation.

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The report, which also encouraged companies to be transparent with the public about their progress, emphasized the potential of autonomous vehicle technology to cut down on the tens of thousands of traffic fatalities each year.

"Automated vehicles that accurately detect, recognize, anticipate and respond to the

movements of all transportation system users could lead to breakthrough gains in

transportation safety," according to the report. "Their potential to reduce deaths and injuries on the nation’s roadways cannot be overstated."

The new guidelines received a perhaps not surprising thumbs-down from some noted critics.

John Simpson, director of Consumer Watchdog's Privacy Project, said that companies developing self-driving technology had been lax in self-reporting to date, reinforcing the idea that voluntary guidelines, rather than requirements, do not work. He noted that only a few companies had produced any public reports at all.

"All the ones that I’ve looked at … really they read like slick marketing brochures," Simpson said. "Over 50 companies have permits (in California to test), if these wonderful self-assessments ... were working, they'd have over 50 self-assessments."

Cathy Chase, president of Advocates for Highway and Auto Safety, called the guidelines weak and noted that cars with self-driving capabilities had been involved in "multiple crashes that have resulted in at least three fatalities."

"The public needs and deserves the U.S. DOT to effectively evaluate and regulate these vehicles before they are sold and used on public roads. Unfortunately, today’s unenforceable guidelines do little to prevent more deaths and injuries from happening," she said.

Michelle Krebs, executive analyst for Autotrader, however, said it was good to see the department step in with guidance as Congress struggles to pass legislation for self-driving vehicles.

"Regulation in this space will be necessary eventually. And while these guidelines are certainly nothing more than suggestions and will need public review, it is important that the government try to keep pace with the technology," Krebs said.

And Alliance of Automobile Manufacturers CEO Mitch Bainwol praised the effort, saying "the updated AV Policy Guidance (3.0) builds on previous guidance Secretary Chao released last September — which has provided greater clarity to auto manufacturers and technology providers working to develop cutting-edge technologies that can enhance roadway safety, expand mobility, and ensure that the U.S. continues to lead the development, testing, and deployment of lifesaving technologies."

Contact Eric D. Lawrence: elawrence@freepress.com. Follow him on Twitter: @_ericdlawrence.