Traffic courts are the end point of a revenue supply stream. Judges do not make, "Gee, was there a valid reason?" types of decisions. They make "Is it humanly possible to apply this law here and are all the 'T's crossed?" types of decisions.
The enforcement and fee structure of our traffic laws are based on extremely low chances of getting caught. If every possible infraction was enforced in every possible instance the average driver's license would be ticketed to the point of suspension within an hour. The policeman is the point were discretion should be applied to decide, "Should I enforce this", and the idea that infractions should be blanket enforced by an automated, 1984ish, mechano-fascist system is insane.
Also there is a general "knowledge" that speed is the ultimate "safety sin" that is so far from correct. The government's own NHTSA report that was released after 10 years of the "55 mile-an-hour limit" had background data that when analyzed (by someone other then the government) showed that the safest speed to be traveling was 5 to 10 mph faster then the general flow of traffic. That same study "proved" that 55 saved lives: after ignoring any other possible source for a reduction in deaths per mile such as much safer cars, massive improvements in tire safety, seat belt laws, etc... So after going with the spin that nothing else could have effected the number of fatalities, the best number they could come up with worked out to it costing an additional 150 man/years (from the reduced speeds) on the roads for every life saved. (One independent analysis pointed out that you could get the same expected reduction in fatalities by increasing the actual tire pressure in all cars by about 2 psi.)
When a more sensible look is made at the data, it is pretty clear that once you factor out increases in passenger car safety, tire safety, and seat belt use, it shows that drivers had become worse, most likely because they had lost driving ability and when at a slower pace it encourages people to do "other things" besides drive.
Lets be serious. Traffic enforcement is about revenue. Speed is easy to prove, it is fun/interesting for cops to enforce and the public has been led to believe that SPEED is the big scary thing, ... and lets be honest, there is something in the back of the average person's head that doesn't want someone to pass them. If speed was the CAUSE of an accident then there would be a speed where when you reached it the accident would ensue.
If traffic enforcement was about "safety" there would be a mandate to enforce the laws as they relate to the generation of accidents: Failure to yield right-of-way, inattentive driving, and just plain incompetence.
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Oh, and the correct civilian use of drones is to create an open source project of mesh networked drones to monitor our government...
And that includes detecting speed traps from above!