Just a day after the Republican chairman and a Democratic member of the Senate commerce committee announced they were working on a bipartisan bill on self-driving cars, the House commerce committee held a two-and-a-half-hour hearing on the deployment of autonomous vehicles.

During the hearing, stakeholders like General Motors, Volvo, Toyota, Lyft and policy think tank Rand Center offered testimony on how the parties think the federal government should regulate the new technology.

It was more of the same from most of the players: They don’t want a patchwork of state regulations, and they don’t want the federal government to dictate what kinds of technology they should use in their autonomous systems.

There was a lot more said, but a crucial five-minute back and forth between the panel of stakeholders and Michigan Rep. Debbie Dingell clearly laid out the work policy makers have ahead of them.

The biggest takeaway is that, today, we have no way of measuring whether an autonomous vehicle is as safe as or safer than a human-driven car, and we haven’t yet determined how much safer an AV has to be.

Here’s an annotated (and slightly truncated) version of that discussion:

Here’s who was on the witness panel at Tuesday’s hearing: Mike Ableson Vice President of Global Strategy, General Motors Full opening statement Dr. Nidhi Kalra Co-Director and Senior Information Scientist, RAND Center for Decision Making Under Uncertainty Full opening statement Anders Kärrberg Vice President of Government Affairs, Volvo Car Group Full opening statement Joseph Okpaku Vice President of Public Policy, Lyft Full opening statement Gill Pratt Executive Technical Advisor and CEO, Toyota Research Institute Full opening statement

Rep. Dingell: As I mentioned in our opening statement, it’s critical to ensure that automated vehicles are truly safe before they’re available to consumers, but we also need to ensure there aren’t any barriers that would prevent life-saving technology from bringing benefits to society as a whole. And I want to be really clear here — we should never let an unsafe or unproven vehicle hit the road. Our challenge as Congress is how to strike the right balance between supporting innovation and making sure consumers are safe.

Do you agree that Federal Motor Vehicle Safety Standards need to be updated in order to support the deployment of automated vehicles?

Everyone: Yes.

Context: The Federal Motor Vehicle Safety Standards are regulations that dictate the design, performance, durability and construction of vehicles on the road today. Before first sale, automakers have to make sure the car meets these standards.

Rep. Dingell: It is my understanding that a rulemaking by the National Highway Traffic Safety Administration to update the Federal Motor Vehicle Safety Standards will take several years. If that rulemaking were to commence today, that it’s likely not to be completed by the time many in the industry have announced that you want to deploy automated vehicles. Is that correct?

Everyone but Gil Pratt of Toyota: Yes

Pratt: I’m not sure; the reason I’m not sure is that I would hope that NHTSA, if the need were great enough, could speed up its actions, but if it couldn’t, the answer is yes.

Context: Today, many of the players either building the vehicle or developing the autonomous technology (or both) have plans to have self-driving cars on the road by 2021. Rulemaking could take anywhere from several months to several years, depending on the complexity of the topic — and regulating self-driving tech is no easy task. Without an update, car makers can’t sell these cars and in some cases can’t get consumers in them in any way.

Rep. Dingell: I understand NHTSA has the authority to exempt motor vehicles from safety standards based on a number of factors, but this exemption authority is limited by law in amount and duration. Could expanding this authority provide an interim path to AV deployment during this rulemaking we just discussed?

Everyone but Dr. Nidhi Kalra of Rand Center: Yes.

Kalra: It’s more complicated than the number of vehicles right now; there’s no reason to think that limit will be hit. Equally important is to think about on what basis those exemptions will be granted, given that most of the time, when one requests that exemption, it’s on the argument that the vehicles are just as safe or safer, and there’s no way to show that, and that would be an equal concern as the number of vehicles.”

Context: A huge part of Kalra’s opening statements centered on the idea that policy makers have yet to lay out how companies should define the level of safety and performance of their vehicles. Today, there’s no way to measure how much safer an autonomous car is than a human driver. The big question regulators have to answer then, according to both Pratt and Kalra, is how safe is safe enough, and how do we measure that?

Dingell: We’ve had a good discussion about a few proactive things that the federal government should be doing. Are there any specific things that Congress should avoid doing that would stifle the development of autonomous vehicles?

Mike Abelson of General Motors: We don’t want to see the government take steps to specify a specific technology or a specific solution as long as we keep in mind that the goal is to prove the vehicle is safer than drivers today. I think NHTSA guidelines are a very good step in that direction in that they don’t specify technology, but specify what the expectations are when the vehicles are deployed in a driverless fashion.

Anders Kärrberg of Volvo: We would not like Congress to engage in traditional rulemaking. It would take a much longer time. It’s clear that technology neutrality is important. Politicians should not pick winners and losers when it comes to technology; that should be done by the industry.

Kalra: Technology neutrality is important, and so is developing regulation that is adaptable and flexible and is designed to keep up.

Pratt: Evidence-based approach is really the best one, where the government sets the criteria for performance and that’s done at the federal level but does not dictate what the ways are to meet that particular level of performance.

Joseph Okpaku of Lyft: [We have concerns with] even with the most well-intended law inadvertently precluding or restricting potential innovation.

Context: While there’s largely an industry consensus on the inevitability of self-driving cars, many automakers and tech companies disagree on the technology that is necessary for operating an autonomous system. Tesla, for instance, doesn’t believe there is a need for laser-based radars. On the other hand, other automakers feel vehicle-to-vehicle communications are just a redundancy in the autonomous system, not a necessity. These players are trying to avoid a federal mandate on what technologies are required and instead want to have the freedom to meet general performance and safety standards as they see fit.

Update: This post was updated to reflect that some automakers feel vehicle-to-vehicle communications are a redundancy.

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