Safety officials are struggling not only with new technology in the auto industry but also with Tesla in particular, an automaker that “thumbs its nose at NHTSA on a regular basis,” said Phil Koopman, a professor and autonomous technology expert at Carnegie Mellon University.

So, in its negotiations with Musk, why did NHTSA not require that FSD or the defective functions be turned off while Tesla attempts a fix? NHTSA won’t say. Koopman, emphasizing he’s only speculating, said it’s possible NHTSA feared being sued by Musk, which would require a huge commitment of resources and would drag out the situation.

“NHTSA would be motivated to get this thing fixed in a way that involves the least trauma and gets it done faster,” Koopman said.

Bryant Walker Smith, law professor at the University of South Carolina, said regulators are just coming to grips with the recent radical changes in automotive technology. Even the term “recall” is becoming outmoded: The Tesla fix will be delivered wirelessly to cars wherever they are through what’s called over-the-air software delivery. Smith proposes the term “virtual recall.”