The logic of Speeding

Have you ever reasoned in this way before? :

Police radar guns are not completely accurate and have a margin of error. Suppose that the margin of error is something like 10%. So as long as I stay within 10% of the speed limit, the police will not book me for speeding. For example, if the speed limit on the highway is 90km/h, as long as I stay below 99km/h the police will have no right to stop me.

This reasoning is actually flawed. Suppose that the radar gun actually has a 10% margin of error. That means that its speed reading may sometimes be 10% higher or lower than your actual speed. So if you are travelling at 99km/h, it is possible for the radar gun to give your speed as 99x110%= 108.9 km/h. That will quite likely get you a ticket!

Just some food for thought.