Thers a couple of points I'ld like to make.
1) The Speedometer in any car is mass produced and not accurate (i.e. it could say your are going 30mph, but in fact could be +/- 5 mph), if its + 5mph you could get a speeding ticket, bit unfair.
2) on the subject of speed cameras, a work college of mine was sent a speeding ticket. Now he ask to see all infomation an the cameras calibrations dates, and that of the equipment used to calibrate it, it was out of date and the case thrown out of court, had he not bothered he would have been fined. (by the way his car could go the speed they claimed its a heap.

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