Many speeding tickets are issued as the result of motorists being clocked with devices that measure how fast a vehicle covers a known distance.

Because some judges and district attorneys are not comfortable with mathematical calculations it is important for the well-prepared defendant to present mathematical based arguments in the simplest of terms. We will start from the end and work backwards.

A vehicle moving one mile per hour will cover 1.47 feet in one second.

If you wish to determine how far a vehicle will travel at a specific speed just multiply that speed by 1.47 feet. For example, if a vehicle is traveling 60 mph it will cover 88 feet in one second. Obviously, it will cover 176 feet in two seconds, etc.

If you are trying to determine how many seconds it would take a vehicle to cover a known distance at a specific speed just divide the distance by the speed and divide the result by 1.47 feet.

This will yield the number of seconds it would take the vehicle to cover a known distance at a known speed.

For example: A vehicle traveling 60 mph will cover 300 feet in 3.4 seconds—-300 divided by 60 divided by 1.47 = 3.4 seconds. If need be you can verify this calculation by multiplying 3.4 seconds times 88 feet (the distance traveled in one second at 60 mph) and the result brings you back to 300 feet.

If you are challenged on the validity of the 1.47 feet per second figure you can prove its validity in very simple terms.

There are 5280 feet in one mile so a vehicle traveling one mile per hour will cover 5280 feet. There are 60 minutes in one hour so a vehicle traveling one mile per hour will travel 1/60th of that distance in one minute, or 88 feet. There are 60 seconds in one minute so a vehicle traveling at one mile per hour will cover 1/60th of the distance it covered in one minute, or 1.47 feet.

You could also state that there are 3600 seconds in one hour and divide that number into 5280 feet and the result would be the same, 1.47 feet.

Once the court accepts and understands the source of these numbers you can apply them to your defense.

If you receive a VASCAR ticket you should obtain a description of the distance over which you were clocked, the time it took your vehicle to cover that distance and the speed you are charged with traveling.

If the citation or incident report claims you covered 300 feet in 4.2 seconds and you are being charged with speeding at 60 mph in a 50 mph zone you can readily verify the accuracy, or lack thereof in this case, of the speed you were claimed to be traveling.

At 60 mph you would have traveled 370 feet, not 300 feet. However, at 50 mph you would have traveled 309 feet in 4.2 seconds, indicating that you were driving within the speed limit.

Even if the calculations indicated the error was in the opposite direction, that your speed was underestimated, the speed-reading should not be allowed as evidence against you, thus eliminating the prosecutions principal evidence against you.

In other cases involving radar or pacing, time over distance calculations can prove serious inconsistencies in the officer’s testimony.

If the officer testifies that he clocked your vehicle for 5 seconds and you were going 80 mph, you can prove, by using time over distance calculations, that the officer could not have seen you for more than two seconds, because of a curve or sign, if you had been traveling 80 miles per hour.

For more advice on how to fight an unfair speeding ticket, consider joining the NMA.

Image Credit: JonOakley