It seems like something that didn't need to be said. That is, until two Tesla vehicles crashed — and one driver died — with the semi-autonomous driving system engaged.

U.S. Transportation Secretary Anthony Foxx called on carmakers to focus not on making cool tech to impress buyers but rather safe automated driving systems during his keynote address at the Automated Vehicle Symposium in San Francisco Monday.

“Sometimes the coolness of the technology may drive people to push the limits beyond what manufacturers have intended,” Foxx said. Adding: “We need to think about that even as we build these systems. We must consider not just what’s within the scope of their intended use, but within the uses that can be reasonably foreseen.”

“We don’t want to replace crashes that occur based on human factors with large numbers of crashes caused by systems.”

Right now, human error alone accounts for 94 percent of all traffic crashes. If humans are entirely — if not mostly — removed from driving duties, it stands to reason roadways would be safer.

In fact, Foxx imagines a future in which highly automated and self-driving car systems could reduce traffic collisions by as much as 80 percent. However, unless all carmakers agree to implement semi- and fully autonomous tech conservatively and with extreme caution, that future may never come to pass.

“We don’t want to replace crashes that occur based on human factors with large numbers of crashes caused by systems,” Foxx said. “So, the challenge would be for us to think about how we integrate these technologies.”

Lawmakers have been hesitant to legislate autonomous driving systems, a technology seen as a safety benefit, for fear of stifling its development and implementation. If crashes like the two involving Tesla's Autopilot continue to occur, however, it might force their hand to craft rules that reins in not just a single bad apple but the industry as a whole.

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