"By the same logic speed cameras should only be sited where there is a problem, such a problem being many accidents or excessive speed for the location."

Thats exactly how locations for fixed cameras are chosen - evidence of excessive speeding by a large number of drivers. A significant number of people killed or seriously injured as a result of accidents.

Edited by daveyjp on 22/11/2017 at 08:04

I think some of the complaints in this thread are aimed at mobile speed cameras, which are presumably sited for the same reasons but are less predictable, and presumably are not known to the satnavs which sound a warning?

Mostly they are, which is why it pays to keep your stand alone satnav updated, and even if not using it as a sat nav, some (probably most) decent models, if set to ''traffic search'' which is where the company issued unit in my lorry is permanently set, will give audible warnings of fixed and regular mobile camera sites as you approach.

Unfortunately if on national traffic search it doesn't tell you the current speed limit, which it and most satnavs do if you just have it running without a destination set, but then you arn't on pre traffic search, can't win them all.

I prefer 'traffic' because i can scan the whole country in seconds, which is especially useful with early starts seeing as how so many motorways and truck routes are closed overnight for road worlh these days.

Edited by gordonbennet on 22/11/2017 at 10:18

I can only speak as a very high mileage driver.

An experienced driver is constantly scanning for things such as moving shadows behind cars/trees, odd lights appearing on parked vehicles, stray animals and the hundreds of other things we are looking for at any moment, especially in built up areas, most of us have the common sense, as said, that we would''t actually need posted speed limits, we're going about at a sensible speed for the prevailing conditions which is often well below the limit anyway.

The world isn't perfect and neither are we, we're better off looking for all the hazards that an experienced driver is, at all times, than we are wasting the valuable seconds checking speedos and looking for cameras, constantly refocusing in case we happened to have drifted over by a fraction.

We arn't calculating 10% + 2 and trying to keep below 35, most of us are trying our best to stay under 30 in 30 zones, treating it as a limit not a target.

It strikes me that much of the debate here (such as setting satnavs to warn the driver of camera locations and the siting of fixed and mobile cameras) centres around avoiding being caught speeding. The emphasis should be on avoiding speeding. Then you won’t get caught.

Like it or not Parliament has decided that it is against the law to exceed the speed limit. Harping on about the “unfairness” of the various detection methods employed and the relative lack of enforcement of other offences is misplaced. As has been said, most speedometers usually over-record the real speed (they must not, by law, under record) and driving within the limit is part of the skill required to drive.

Just as an aside the “leeway” that is the original subject of this question is not there to provide an increase to the prevailing legal limit. It is in place to avoid excessive numbers of frivolous challenges being mounted against prosecutions where the accuracy of the measuring method used may be called into question. The principle is that where a driver claims he was not exceeding the limit the device must be shown to be considerably more inaccurate (and thus harder to discredit) if it shows the vehicle’s speed at (Limit + 10% +2mph) than it would be if it shows the speed at (Limit + 1mph).

When I've been driving in France I've observed that as I approach many towns / villages with, say a 50 kph limit, there is another roadsign posted a couple of hundred metres before entering the speed restricted area - warning of the upcoming limit, so avoiding the issue of drivers feeling that they have been caught out by an unforeseen speed limit.

"Similarly, the ‘I was only just in the 30 zone’ argument is plain wrong."

I hope that is not a reference to my post higher up. I was very aware that this point might come up and carefully avoided any justification of my speeding; the details I gave were simply to put my offence into some context. I was caught "bang to rights", as I said.

Yes, I did say I wasn't feeling contrite - maybe that's what has irked some posters. There is a difference between legality and morality, though the former reflects the latter, often with some gap between them as time passes and certain things that were regarded as awful become less so - and the reverse happens, too.

In the circumstances under which I was caught I'm afraid I wasn't at all upset at having offended - more irritated with myself for allowing it to happen. I should have done better.

I shall continue to strive to drive within the law.

My first speeding fine was in the late 1950s. I was riding my motorcycle which I had just serviced, among other things adjusting the chain and tappets. It made the motorcycle much quieter. I realised that somewhere along the way I had learned to judge the speed by hearing instead of keeping an eye on the speedometer. I asked the very polite policeman (in a Humber Super Snipe) if he would drive in front of me at a steady 30 mph so I could see how accurate my speedo was. My speedo matched the Humber exactly.

My second fine was in Broken Hill, Zambia in the late 1960s. I had broken down on approaching BH, a trivial thing, a broken wire, and a Zambian driver had stopped to help and pointed out the wire. I was driving down the main street looking for the other driver so that I could thank him when I went through a radar trap doing 40 in a 30 zone. I knew that I was doing 40 but the senior police officer in charge of the radar said I had been doing 50. No point arguing.