U.S. safety investigators last week issued their strongest recommendation yet on how to curtail distracted driving: ban all use of mobile devices behind the wheel, including those that offer hands-free calling or texting.
The National Transportation Safety Board is asking all 50 states to implement the ban, which is far tougher than restrictions put in place in many states that prohibit handheld phone calls or texting while driving.
If the NTSB gets its way, technologies such as Ford Motor Co.'s heavily marketed Sync, which promotes hands-free calling, are at risk because they are built around drivers connecting their smartphones to the car.
In-car systems such as those offered by Audi, BMW, Hyundai, Chrysler and Toyota also would be affected if states were to adopt the agency's recommendations since the systems offer similar mobile phone-based features.
The five-member board also is calling on the telecommunications industry to develop technology that disables a driver's phone while the car is moving.
For now the NTSB's idea seems little more than political advocacy since the agency's recommendations don't carry any regulatory weight.
But the call for a nationwide ban is taking the debate about in-car cellphone use in a new direction and is calling into question whether the hands-free solution many automakers have proposed to combat driver distraction is indeed safe.
The NTSB's plea also could lead to legislative action by Congress or regulatory action by the National Highway Traffic Safety Administration, which also has made distracted driving a priority.
For now, many automakers use the smartphone as a bridge that gives drivers access to Web pages, navigation maps and other features from the instrument panel or by speaking aloud.
"There are billions of dollars of smartphone development activity that would be thrown out the window," said Roger Lanctot, a technology analyst with Strategy Analytics.
"You'd have a lot of dark screens in cars," he added.
As envisioned by the NTSB a ban would allow exemptions for built-in mobile devices, such as General Motors' OnStar, and navigation systems that "aid the driving task."
But any in-car technology with Bluetooth connectivity, which allows drivers to place and receive calls without having to touch their phones, wouldn't be allowed.