Hi

My son was pulled over for speeding.

The police said that he was doing 55mph in a 30mph limit so would be referred to court.

My son is adamant that he was not doing 55mph inside.

The police statement says they were standing approximately 300m inside the 30mph zone.

We have measured where they said they were standing and it is only 242 metres inside the zone.

They have sent a photo of the reading on the hand held device

- besides the mph it also says 248.2 m which we assume is how far the reader was from the car when zapped?

which would mean my son was outside of the 30mph when zapped.

Should he plead not guilty?

He is within 2 years of taking his test so if he is given 6 points we think he automatically loses his licence?

Thanks in advance

I'm afraid that this answer isn't going to help your son very much, but it does pose some questions and give you an idea of what might happen.-

Your measurements seem very precise.

If they are that accurate then your son is not guilty of the offence for which he has been summonsed.

However, how to you know exactly where the police officers were standing?

We are after all only talking about 6.2m here, so there would have to be a margin for error unless you can be absolutely 100% certain.

-

Also, if the 30mph gateway is at a distance of 242m and your son was measured at 55mph at a distance of 248.2m...

At 55mph, the vehicle is travelling at 80 feet/s. (6.2m in feet is 20.34).

This means that the vehicle will need to have lost 25mph in the space of just over 20ft.

Even the most efficient braking system on your average road vehicle would not be able to manage that.

So, if the brakes were 100% efficient and were stamped on and assuming the vehicle has anti-lock brakes, the vehicle would lose about 16 feet/s.

The velocity of a vehicle at 30mph is 44 feet/s.

At 6.2m away from the 30mph gateway, this means that the vehicle would have 1.27 seconds to scrub off 25mph or 36 feet/s. At that distance, the vehicle will only have lost 20.32 feet/s which means that its velocity would be 59.68 feet/s or 40.7mph as it passed through the 30mph gateway.

-

The Magistrates sentencing guidelines say...

In a 30mph area at between 31-40mph they should impose a Band A fine and 3 penalty points.

In a 30mph area at between 41-50mph they should impose a Band B fine and a disqualification of between 7-28 days or 4-6 penalty points.

In a 30mph area at over 51mph they should impose a Band C fine and a disqualification of between 7-56 days or 6 penalty points.

However, the Magistrates do have a certain amount of leeway and I've seen new drivers get 5 points and a higher fine for similar or a 7 or 14 day ban and no points. But that really depends on the Magistrates and what kind of day they're having!

Thanks Dragon Fly.

We have measured with a trundle wheel and an online map app.

The police stated in which drive way they were stood and we have taken the worst measurement from the furthest side of the driveway, even though my son said they were stood behind the nearest end.

Rather than plead not guilty do you think he should plead guilty and put something about this in his mitigation so they are more lenient?

I have a feeling the police knew that it was very close to the limit as I would have thought they would have said approx. 250m otherwise? approx. 300m to me is 280-320, not 240?

The statement is also misleading as it makes it seem as if my son was 300m within the limit.

I know in law it doesn't matter how far inside you are but surely its worse that far in to the village, rather than at the 30mph limit sign?

PS Just noticed I put 'be laser' not 'by laser' in the heading - that will be the Cornish in me!

PS Just noticed I put 'be laser' not 'by laser' in the heading - that will be the Cornish in me!

Fixed that for you

Can't fix the problem your son is having. I doubt very much that he will get off without points and a fine when it goes to court.

To be honest, I'd take all of your measurements and anything else you have to the court and speak to the bod from the CPS on the day. I've double checked my figures for feet/s and mph as well. They are accurate.

Assuming what you say (bearing in mind we only have one side of the story) is correct, start with asking them to offer no evidence (extremely unlikely, but it's worth a try) and failing that they may accept a guilty plea to a lower speed as your son crossed the 30mph gateway. It's not outside of their powers to do this, so there's always a chance. And given that your evidence/findings may cast doubt on their case, they are more likely to accept that he would have only been travelling at 40mph as he crossed the 30mph gateway. That could still result in 6 points though (loss of licence as a new driver)

Your sons only other hope is to plead not guilty. Again, assuming that what you've said is correct, then technically he's not guilty of the offence for which he's been summonsed (however, had the police officers waited a few metres, he certainly would have been guilty of speeding 40 in a 30 (at least)).

Be warned though, if a not guilty plea is entered and then your son is found guilty, the fine and points are likely to be at the higher end of the spectrum, which will almost certainly mean that your son will lose his licence and will need to take his driving test again.

Don’t you just hate those speed limit signs that jump out without warning at you.... nearly as bad as invisible policemen with radar guns....

Or was he just driving like every teenage boy and you’re trying to wriggle him off the hook?

there are practical problems with hand held devices that can make a massive difference to the reading.

For example if the bean first hits the bonnet but is then moved to the windscreen or even moves from the moving vehicle to something stationary nearby. The angle between the moving vehicle and the user of the hand held device.

I would suggest that at 250m away the police officer was incapable of holding the laser still to a matter of 4 minutes of angle (ie height of bonnet or screen at that distance) on a moving target when a military marksman would only be expected to hold a rifle to 2 minutes of angle on a stationary target from the prone position.

I would suggest that the reading used was only one of a number that flashed up when the laser gun was being used and happened to give the highest reading even though this would be actually the least accurate.

Your problem though is that Magistrates dont want to listen to anything that would throw doubt on the dozens of similar cases they had decided upon previously and you certyainly wont be given any of the other data from the speed gun, that has long been deleted as "irrelevant".

Even the static radar speed traps are up to 10% inaccurate on the best of days but you wont get anyone to take this into account.

If they concede a 10% error then that will still mean he gets done for doing 50.

I wish you luck as that is what is needed as well as a tame physicist to point out how these things work or dont work