Procedure…………. Speed offences.

I think whatever we do in life we are governed by procedure.  Do you get up in the morning at the same time, wash,
shower, breakfast in a certain order? We are creatures of habit essentially.  A rather arbitrary introduction at present.  Courts and the law they oversee are also covered by procedure whether they be Magistrates Court or up to and including the House of Lords.  The rule of law and the importance of following it can and does make the difference between a guilty or not guilty verdict.  For if there is not a foundation in law then the legal goal posts will forever shift in the sands of uncertainty and ambiguity.

I use the above paragraph to introduce traffic law.  Traffic offences are slightly different to other criminal offences in that as a driver you have either committed an offence or you haven’t. Rarely is there a need to prove an intention, a mindset or ability.  It is an objective test.  So traffic offences, on the face of it should be fairly easy to bring to a conclusion.  I don’t think there is an area of law that has so much case law written about it and I cant think of a “what if” scenario that hasn’t been covered. So far so good.  HOWEVER, traffic law is like trying to memorise a telephone directory.  Because it is black and white, the traffic officer needs to familiarise  themselves with that directory.  I have been in court where the judge has allowed evidence on other criminal matters, despite the fact that perhaps it wasn’t gathered correctly.  To do so in traffic related matters is usually terminal to the case. Traffic law is very much based around procedure.  There are rarely very few defences availed because I as I have previously stated it is an objective test.  However, duress is a good staring point.

With that in mind I introduce the topic of speed offence’s. A minefield of legislation in its own right.  Perhaps it would be a good starting point to outline the three principal speed detection devices.  The most obvious is the roadside fixed site yellow GATSO camera’s.  Secondly are the mobile speed detection devices operated by police officer’s.  Less common is the VASCAR distance measuring equipment fitted to police vehicle’s.  All three devices use the recognised practices of maths and physics in that speed equals distance divided by time.  In collision investigation this is broken down further into scalar and vector quantities but this is beyond the scope of this article. I will concentrate on the first two methods of speed detection because they use the same method of measurement, that being LASER.

The method of measurement was originally developed by NASA in the run up to the moon landings.  However their purpose was to accurately measure the distance from the earth to the moon.  Essentially the speed of light (approximately 186,000 miles per second) is constant. The beam is pulsed many times a second and the difference in time it takes between each pulse for the LASER light to be reflected back to earth is then measured to calculate the distance (= Speed x time ).  With simple transposition of the equation a speed could be established.  Thus the “LASER gun” was invented. Both the fixed and mobile speed detection devices work on the same principle.  VASCAR is slightly differently in that it still uses the same applied mathematic principle it compares the average speed between two fixed points using distance and time.

Fixed roadside device’s (which also include the mobile yellow vans you see at the side of the road) and police operated mobile device’s are slightly different.   ACPO has set the speed thresholds at 10% + 2mph over the red ring limit.  The first two methods of operation do not need to form an opinion that the motorist is exceeding the speed limit. They can target their LASER on any vehicle that passes them.  A police officer using a mobile LASER device must form the opinion that a motorist is exceeding the speed limit before measuring the speed with the device.  How does the police officer do this?  Well the list is endless but an obvious opinion would be that the target vehicle was overtaking other vehicles.  Forming the opinion of speed however is very important.  Legally police officers cannot blanket “ping” every vehicle that passes by them.

Assuming that the Officer has correctly formed the opinion of speed then comes the situation of calibration checks.  This, more than any other has caused a case to be thrown out of court.  The device itself must be within its calibration certificate dates.  The Officer before using the device must conduct a certified distance check.  Usually located within the police station grounds, two marks at a set distance apart will be used to check the accuracy of the device.  It will come as no surprise that the distance between the two marks has also been calibrated and certified. Once that has been done and the Officer has recorded the fact the speed measuring device is taken to its intended location. Once there a further distance check is conducted against an immovable object and the readings are again recorded.  The speed recording session is undertook, with every offender’s readings recorded, being speed and the distance at which that reading was taken.  There is a common fallacy that the offender must be shown the readings from the device. Whilst it is aways preferable to do this, there is nothing in law to say that it has to be done.  Once the check site has been completed a further distance check is done on immovable object and recorded.  Before the end of tour the Officer will conduct another certified distance check, which is again recorded.

Why is so much effort placed on doing these checks?  Remember earlier on that I said that the Officer has to form an opinion of excess speed?  In law this MUST be co-oborrated by another means.  There is one exception which I will cover in a moment.  If the accuracy of that co-oborration is in doubt then the whole case falls.  The opinion of speeding is not enough.

So what is the one exception to the co-oborration of speed?  When the offence is committed on the motorway.  I merely have to form the opinion of speed in that the driver was overtaking other vehicles and no other vehicle overtook it.  Simplistic, but in essence there it is.  Of course the more co-oberrative evidence I have the better but unlike in the first example it is not mandatory.  Since motorways always attract high speed if I wanted to ban a driver from driving because the speed was so high then I would have to  prove beyond a reasonable doubt that threshold.

Many speeding offences are lost at court because the calibration checks weren’t carried out or if they were they weren’t recorded.  Another common failing is lack of production of the relevant calibration certificates.  If all the relevant criteria have been met it is very unlikely that a driver would be able to wriggle out of a speeding conviction.

Finally a story that is legend within the road policing community and that of the Royal Air Force.  I kind of hope it’s true.

Two British traffic patrol officers from North Berwick were involved in an unusual incident while checking for speeding motorists on the A1 Great North Road. One of the officers used a hand held radar device to check the speed of a vehicle approaching over the crest of a hill, and was surprised when the speed was recorded at over 300 mph. Their radar suddenly stopped working and the officers were not able to reset it.
Just then a deafening roar over the tree tops revealed that the radar had in fact latched on to a NATO Tornado fighter jet which was engaged in low flying exercise over the Border district, approaching from the North Sea.
Back at police headquarters the chief constable fired off a stiff letter of complaint to the RAF Liaison Office. By return came the reply in true laconic RAF style:

“Thank you for your message, which now allows us to complete the file on this incident. You may be interested to know that the tactical computer in the Tornado had detected the presence of, and subsequently locked onto, your hostile radar equipment and automatically sent a jamming signal back to it. Furthermore, an air-to-ground missile aboard the fully-armed aircraft had also automatically locked onto your equipment. Fortunately the pilot flying the Tornado recognized the situation for what it was, quickly responded to the missile systems alert status, and was able to override the automated defence system before the missile was launched and your hostile radar installation was destroyed. Good Day”


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