I don't know about the US, but was a recent news story that in the UK they will be able to drive 10 mph faster than the speed limit (16 kph) for safety reasons because sometimes it would increase the risk of an accident if they travel at a significantly slower speed than the other vehicles when other cars are traveling slightly over the speed limit.
See: Google’s driverless cars will EXCEED the speed limit, says engineer
I think that 10 mph is the amount of leeway you have before they prosecute. So, as long as they know the speed exactly enough to be totally sure that they are no more than 10 mph faster than the speed limit, they wouldn't be prosecuted.
If you go a bit faster than that, in the UK, than 10 mph but less than 10% faster then - from news stories - in some places anyway, you can opt to do a speed awareness course instead of fines and points (not sure how that would apply to a self driving car :) ).
See: Drivers who exceed speed limit by more than 10mph will escape points and fines
WARNING - Not to be taken as legal advice for drivers, and what I say could easily be out of date!
See: Google’s driverless cars will EXCEED the speed limit, says engineer
I think that 10 mph is the amount of leeway you have before they prosecute. So, as long as they know the speed exactly enough to be totally sure that they are no more than 10 mph faster than the speed limit, they wouldn't be prosecuted.
If you go a bit faster than that, in the UK, than 10 mph but less than 10% faster then - from news stories - in some places anyway, you can opt to do a speed awareness course instead of fines and points (not sure how that would apply to a self driving car :) ).
See: Drivers who exceed speed limit by more than 10mph will escape points and fines
WARNING - Not to be taken as legal advice for drivers, and what I say could easily be out of date!
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Robert Walker
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