While the rest of the autonomous drive technology sector dials back its ambitious deployment plans, Tesla is still charging ahead. During Tesla's "Autonomy Day" presentation CEO Elon Musk said the company's controversial Full Self-Driving option will be "feature complete" by the end of this year, and that "by the middle of next year, we’ll have over a million Tesla cars on the road with full self-driving hardware, feature complete, at a reliability level that we would consider that no one needs to pay attention."

Assuming Musk's predictions are accurate, only one thing seems to stand in the way of this monumental achievement: the need for "regulatory approval." Musk has repeatedly referenced this potential barrier in public comments about Full Self-Driving, mystifying many in the space who are all-too aware of the fact that there is no reference to autonomous vehicle software in the Federal Motor Vehicle Safety Standards (FMVSS), with which companies must comply to receive approval to sell a vehicle in the United States. Since Musk has never clarified what he means when he says "regulatory approval," and since Tesla has not responded to The Drive's request for clarification, let's examine the situation as it stands right now.

Though cars are subject to any number of rules established at national, state/province, county and municipal government, "regulatory approval" has a very specific meaning in the auto industry. In order to sell a new vehicle in a given country a national regulator must approve it for sale by ensuring that it complies with the country's rules, which generally focus on safety and emissions. Since autonomous drive technology doesn't effect emissions, "regulatory approval" in the context of the United States (where Tesla sells the vast majority of its vehicles) means demonstrating compliance with the safety requirements of FMVSS.

The Department of Transportation, which issues and enforces FMVSS, has promulgated three sets of guidelines for autonomous vehicles, which are non-prescriptive and entirely voluntary. Transportation Secretary Elaine Chao has repeatedly emphasized that she does not want federal rules to "stand in the way of innovation," citing the number of road deaths caused by human error as the reason to avoid any kind of barrier to autonomous vehicle deployment. In fact, one of the Department of Transportation's main priorities for autonomous vehicle policy has been to streamline the process for approving FMVSS exemptions for autonomous vehicles.

If you're thinking "see, there are regulations that affect AVs after all," hold your horses. Those exemptions are for autonomous vehicle designs that deviate from FMVSS rules about things like vehicle control systems, such as GM's plan to build an autonomous Chevrolet Bolt without a steering wheel. FMVSS doesn't say anything about autonomous vehicle software, so as long as Tesla (or any automaker) plans to upgrade its FMVSS-compliant vehicles with software alone, or even hardware like processors that aren't regulated by FMVSS, that update wouldn't require any form of regulatory approval. The same goes for any automaker: if a car has been approved for sale in the United States, it can be upgraded to be capable of autonomous driving as long as that upgrade doesn't alter anything specifically listed in the FMVSS, none of which are directly related autonomous drive technology.

In theory, at least, all this could change at any time. That said, regulators from both the Trump administration and the Obama administration have explicitly expressed the desire to avoid putting up any barriers to innovation in autonomous drive technology. Nor has there been a serious legislative effort to create a regulatory approval process for autonomous vehicles. In fact, the piece of AV legislation that came the closest to passage (last year's AV START Act) actually sought to provide even more exemptions for the human-centric FMVSS rules referenced earlier, actually lowering the barriers to autonomous without traditional human controls. Opposition to such deregulation has been relegated to relatively marginal interest groups like the League of American Bicyclists and representatives of states who have developed their own rules about autonomous vehicles, who were worried by language in the bill that could have enshrined the Department of Transportation as the only body capable of setting standards for AV construction and performance (known as federal pre-emption).

This, of course, brings us to a far more complex issue that Tesla's defenders regularly bring up as an explanation for Musk's comments about "regulatory approval": state laws about autonomous vehicles. 29 states have passed legislation concerning autonomous vehicles according to the National Conference of State Legislators, and 11 more states have enacted executive orders affecting self-driving vehicles. Some of these rules, like legislation passed in Florida and an executive order in Arizona, explicitly allow driverless vehicles on the state's roads. Others, like executive orders in Washington, Ohio, and numerous other states simply order the creation of committees or working groups to study the issue. Some states have passed rules permitting autonomous vehicles provided they meet existing FMVSS and DMV standards or carry specific amounts of insurance, but only a few have rules that impose a meaningful compliance burden on the developers or operators of autonomous vehicles that meet state and federal non-autonomous vehicle rules.

Going into the entire body of state-level legislation affecting autonomous vehicles would turn this into something more than an overview of barriers specific to the deployment of Full Self-Driving, so instead let's focus on the most comprehensive and potentially burdensome set of rules facing Tesla's autonomous plans: California. The home of much early autonomous vehicle development, California's DMV has set the most thorough and far-reaching rules regarding AVs anywhere in the US... inconveniently enough, in the state that has always been Tesla's single largest market. The DMV has set rules requiring permits for autonomous vehicle testing with a human "safety driver," without a human "safety driver," as well as for "public deployments," while the California Public Utilities Commission has an autonomous vehicle pilot permit program under its authority to regulate ride-hailing operations in the state.

Tesla already has a DMV permit to test autonomous vehicles in California, so to make Full Self-Driving available to its customers there it only needs a DMV public deployment permit (Tesla only needs CPUC approval to create a ride-hailing network, not to deliver autonomous functionality that its customers have paid for). This would require Tesla to submit an application outlining the operational domain for Full Self-Driving (presumably everywhere), have the ability to log data and make updates (which Teslas already have), and "certify" that it is satisfied that its vehicles are safe for use on California's roads and meet industry cybersecurity standards. More significantly, Tesla would also have to take legal liability for any property damage, injuries or death caused by its self-driving cars, and provide some form of insurance or self-insurance against that liability. But as long as its vehicles meet FMVSS (which they already do), it submits testing information, provides an educational program to consumers, can communicate owner information to law enforcement and has a "communication link" to a remote operator, "if any."

In short, as intimidating as California's rules might seem they essentially boil down to the same principles of self-certification that essentially every form of automotive regulation in the US relies on. In response to questions about how Tesla might approach the public deployment permit process, DMV Public Information Officer Marty Greenstein tells The Drive that Tesla has extensive discretion to even define its vehicles as "autonomous":