In the case of the appeal against conviction at Allegheny County Court, alot was made of the error caused by the reaction time of the officer operating the VASCAR unit. There is certainly a delay in the time it takes the officer to throw the switch on the machine from when he see's the speeding motorist cross the first reference point. The figure given in court was 0.3seconds. The assumption was that in that 0.3sec the car would have travelled a certain distance over the reference mark before the VASCAR started to measure the time. This would have the effect of shortening the time measured and therefore increasing the average speed over the distance, in this case, 100 feet.

Up to this point there is nothing wrong with the theory, and it would appear that the appeal is sound.

However the one thing that hasn'tbeen taken into account is the delay in the officer switching the stopwatch off, once the car has passed the second reference mark. There is also a delay here. And it must also be 0.3sec. Therefore the two delays have the effect of cancelling each other out. Here's how: Lets say that by the time the officer throws the switch at the 1st reference point, the target vehicle has travelled 5 feet past it. That leaves 95 feet of the 100 feet distance.

When the vehicle passes the second reference point, there is also a delay in the officer switching the switch. Since the delay is the same as the first, the vehcle travels, for example, 5 feet over the mark. Add that to the 95 feet it has travelled since the officer threw the first switch, it gives the 100 feet distance the vehicle has been timed ver. This is what the officer meant in his testimony that 'there is no delay in switching the switches'. What he meant was that there is a delay, but it is cancelled out in the delay in operating the second switch.

In the UK, we are trained over 2 1/2 days to operate VASCAR and only those of us who work on Taffic are trained. We are also given training on how to defend ourselves in court against such defences as the one we have discussed. The fact reamains, speed kills, and even 44mph in a 30mph limit is too fast, since these limits are typically posted in residential areas, and if there's one thing I dread the most is having to deal with a fatal RTA involving a child and then having to tell it's parents that their world is about to fall apart. Please, lets not make the lawers richer, let me have to go and do something other than write speeding tickets and let's all slow down! Safe driving.

Editors' reply:

Dear Dave,

Your point is well taken. Indeed, it may seem quite reasonable to assume that the operator will have the same reaction time starting and stopping the VASCAR unit, thus, eliminating the error from the measurement caused by reaction time.

This, however, may or may not be the case. Just as drag racers will sometimes "red-light" (which is analogous to negative reaction time; "reaction" preceding the event which should trigger it), there is the likelihood of the same happening to the VASCAR operator.

This may not happen very often, in fact, I concede that there may be operators who will never make such an error over perhaps their entire career.

This, however, is beside the point. My point was that reaction time introduces an error, for which the VASCAR speed reading procedure has no control for. The error introduced by the human operator may vary not only between individual operators, but of course it may vary depending on any number of factors affecting human performance in the same individual. It is also not argued whether a particular operator performs poorly - the point is that we never know how well or how poorly.

I believe that no matter what the case, "evidence" that cannot be corroborated or quashed, should not be admitted in the court of law.

I'd also like respond to your second point.

Speed does not kill. Unattentive, incompetent drivers kill.

Of course I do believe that there is a reasonable speed in any particular instance. However, how can you translate this reasonable speed in one number? I don't think it is possible.

I assume you are a policeman. As a policeman, you have probably received extensive driver training. Your driver skills probably far surpass that of most others'. Would you say if being everything else the same, the reasonable speed for you is the same as for my 96 years old grandma? Obviously not. Thus, you may agree, that drivers with different skills, driving different cars, under different conditions on the same stretch of road will likely find different speeds "reasonable". If so, what number to put on the speed limit sign?

In this country, that number seems to be the lowest possible. I don't think it is smart regulation - people come to learn that the speed limit is unreasonably low, and they develop a disregard (they have, it seems) for it. I don't think it is a good system where masses of people disregard posted rules.

A better approach would be to post "recommended" speeds - this may be the mean, or median of observed speeds on a particular road. Should someone cause an accident while exceeding the recommended speed, the burden would be on this person to prove that the accident was not caused by his recklessness (the accident and the higher than recommended speed would be prima facie evidence of recklessness).

I hope you find these points worth of your consideration. I would like to assure you that I do not advocate recklessness by speeding or otherwise, and I do believe that people should be held accountable for causing harm to others. At the same time, a free society must give the choice to its citizens how to run their lives peacefully - or we (I'm afraid) no longer live in a free society.

Again, I appreciate your points - thank you for taking the time to read the story. I am looking forward to your reply.

May I have your permission to post your opinion to the web site?

Sincerely,

Janos Dohanics