You get pulled over when you thought you weren't doing anything wrong. Next thing you know is that the officer is giving you a speeding ticket when in fact you know for sure you weren't speeding according to your speedometer.

Well the fact is that your speedometer may not be completely accurate. You may in fact have been going 45 miles an hour in the 45 mile an hour zone according to your speedometer but in reality were speeding.

If you want to build a defense against this type of ticket you will need to get a speedometer test. You will have to find a local auto shop that has a dynamometer or similar piece of equipment to test the accuracy of your vehicle. They will run a speedometer calibration test to see if it has any problems. And most likely they will offer to calibrate your speedometer while you are already in the shop which isn't a bad idea either.

Make sure that the test results they give you aren't just scratched on a piece of notebook paper, but printed with some sort of seal or certification showing that the results are indeed accurate or at least credible looking.

If you find your speedometer was not working properly, this is going to help you in court. Present the judge with the test results showing that you were not according to your instruments trying to break the law by speeding. The judge will have most likely seen this test before and know which places are credible and take this into consideration.

A couple things will happen here. The ticket may be dropped all together since you weren't willingly breaking the law. The ticket may be reduced to a lower offense. Last, you might get some sort of defective equipment charge which is another type of ticket. The defective equipment charge will be cheaper and in most cases won't cause your auto insurance to rise or add points against your license.