Road Safety News

TfL speed camera claims challenged

Tuesday 27th January 2015

Recent articles in the Telegraph and Local Transport Today (LTT) both scrutinise casualty reduction claims made by Transport for London when it announced plans to upgrade the capital’s speed camera network.

In September 2014, when announcing the upgrade from wet film to digital speed cameras, TfL said: “At locations where safety cameras operate in the capital, research shows that the number of people killed or seriously injured (KSI) fell by an average of 58%, meaning that the cameras help to prevent 500 deaths or serious injuries each year”.

However, on 13 December, the Telegraph columnist Christopher Booker said: “Mayor Johnson’s traffic officials have embarked on a scheme that will do little or nothing for road safety”.

Then, on 23 January, LTT asked whether “Transport for London’s speed camera investment programme is based on a flawed understanding of the evidence about their effectiveness in reducing casualties”.

Both articles originate from information provided by Idris Francis, who has long argued that speed cameras do little to reduce casualties. Both quote data provided by Mr Francis which suggests that the TfL figures “ignore the influence of factors such as regression to the mean and trend”.

Leon Daniels, TfL's managing director of surface transport, wrote to Mr Francis rejecting his claims. LTT quotes an extract from the letter which says: “The effectiveness of safety cameras in reducing casualties at the locations where they are implemented is well established. 

“Our position is supported by a number of studies, including the detailed four-year evaluation of the National Safety Camera Programme, produced for the DfT by University College London and Dr Mountain of Liverpool University in 2005.

“Importantly, this study shows that safety cameras are effective in reducing casualties, even after trend effects and regression towards the mean are taken into account.”

Mr Francis, who has produced a series of graphs plotting the decline in reported fatal and serious injuries across London and at camera sites, told LTT: “As you can see there has been no meaningful difference between the rate at which KSI fell at your (camera) sites and the rate at which they fell elsewhere.”

Christopher Booker in the Telegraph describes the result as “unequivocal”, adding: “The two graphs, though very slightly apart, showed exactly the same rate of decline. In other words, any evidence that cameras affected the accident rate was virtually nil.”

NOTE TO CONTRIBUTORS TO DISCUSSION THREAD: while we welcome comments on this story we ask contributors to please ensure their comments relate to the story itself, and to refrain from 'tit for tat' exchanges with other contributors. We also ask contributors to refrain from multiple posts which repeat that same point(s). Thanks for your co-operation.


Comment on this story
Report a reader comment

What's your view - comment on this story:

I confirm that I have read and accept the moderation policy and house rules relating to comments posted on this website.
Your comment:
Your name and location:
Your email:

This on 20 Sept as I have only just seen your offensive and inaccurate comment. For your information, I DO care about road injuries, I DO care when the authorities spend £200m a year, penalise 1.5m drivers, very few of whom are unsafe,and jail many who refuse to incriminate themselves - and to achieve what? NOTHING, Hugh, ABSOLUTELY NOTHING.

And THAT is why I campaign as I do. You always prefer your own opinions to evidence, as you have again here, but resorting to that sort of offensive abuse is simply not accetable - and I do not understand why Nick allowed it.
Idris Francis Fight Back With Facts Petersfield

Agree (1) | Disagree (1)

I wonder how many speed cameras there would be, if all fine monies went straight to the Treasury including all Speed Awareness Course revenue? Plus all 'administration' costs were taken away from private companies (like ACPO, NDORS etc)and also went to the Treasury?

To re-quote the old saying, "Once an organisation has been formed its primary objective becomes its own survival, not its original purpose" and this sums up the speed camera industry in one sentence.
Terry Hudson, Kent

Agree (7) | Disagree (4)

I disagreed Idris, for the reason given in my first posted comment.

No I didn't read your evidence - I couldn't be bothered to be honest - no doubt it's correct as far as it goes - but you're barely scratching the surface.

Perhaps the ratio of 'disagrees' to 'agrees' also represents the ratio of the number of readers tasked with actually trying to do something about road accidents, to the number of armchair critics seemingly on a mission purely to try and prove the authorities wrong purely for self-gratification and not necessarily motivated by the desire to reduce road accidents.
Hugh Jones, Cheshire

Agree (6) | Disagree (10)

"the number of people killed or seriously injured (KSI) fell by an average of 58%, meaning that the cameras help to prevent 500 deaths or serious injuries each yearĒ

I believe it would be difficult to estimate what any camera benefit may actually be, but to suggest it could be almost 10 times as great as the number of KSI accidents that even have speeding as one factor when others may include road rage, drink, drugs, crime, etc. which any kind of speed management would be unlikely to effect, seems to me to be stark raving bonkers.

Or is this statement just intended to be misleading, such as "the straw I put on the camel HELPED to break it's back"?
Dave, Guildford

Agree (8) | Disagree (4)

Once again I am mystified by being voted down by 6 to 1 when I simply point out the facts, and how to confirm them.

I appreciate that 7 comments is a very small proportion of the readership, but even so, is it not high time that those who disagree with me on proven facts actually started to base their opinions on the truth instead of fantasy and wishful thinking?

One other thing - did anyone who voted "disagree" bother to check the evidence before disagreeing?
Idris Francis Fight Back With Facts Petersfield

Agree (9) | Disagree (9)

Dave is right about anyone here being able to prove me right about TfL, wrong about anyone being able to prove me wrong. Here is how to prove me right, it really is this simple.

Obtain Tfl data from their website - July report.

Add up any parameter - KSI, FSC, etc.- for every year from 1990 to 2012 and enter it in an Excel row.,

Do the same for Stats19 data for London, from DfT web site.

Subtract TfL from Stats19 to arrive at non-site totals.

Draw graphs of site and non-site data on the same sheet with non-site scaled to best fit with site from 1990 to 1992 when there were few cameras.

Now look at the right hand end, 2012. There is no meaningful difference.

There are of course differences in the middle, when sites were being selected for higher than normal numbers, but with few new ones in 2009-2011 that effect disappears.

Meanwhile, TfL continue to claim cameras brought about 58% reductions in KSI even though the same reductions occurred where there are no cameras and remain determined to spent tens of £m more to achieve nothing at all.
Idris Francis Fight Back With Facts Petersfield

Agree (11) | Disagree (13)

Derek: my error - now corrected. Thanks for pointing this out.
Nick Rawlings, editor, Road Safety News

Agree (4) | Disagree (0)

The article refers to published work by Mr. Christopher Brooker. May it please be noted this is incorrect, his name in Booker.
Derek Reynolds, Salop.

Agree (4) | Disagree (0)

Should road safety be politics or engineering? If politics, then trust in politicians and the authorities is further eroded by the unsubstantiated claims that speed cameras improve road safety. If engineering (as I believe it should be), then opinions and good intentions need to be replaced by evidence.

With TfLís cameras itís simple because Mr Francis claims that data on TfLís own website shows no beneficial speed camera effect. I havenít evaluated the data but I suspect each of us could prove Mr Francis right or wrong for ourselves.
Dave Finney, Slough

Agree (14) | Disagree (5)

As I have said repeatedly, I am first and foremost a safety engineer, who has assessed the safety case for speed cameras (and other speed management schemes) and found that the claims for safety benefits are flawed, and actually bogus. I am anti anything that is detrimental to road safety, and speed cameras are top of that list. You made a living from them, so I can see that the exposure of their utter failure will be difficult to swallow. But you'll have to get used to it.
Eric Bridgstock, Independent Road Safety Researcher, St Albans

Agree (14) | Disagree (15)

But Eric, you're an anti-speed camera campaigner (despite your titles), so that's what you're required to say isn't it? Hardly a bombshell.
Hugh Jones, Cheshire

Agree (16) | Disagree (9)

Your posting represents just the sort of wishful thinking that has propped up the multi-million pound speed industry over the years. Put simply, a camera on a pole that causes distraction among all drivers (not just those exceeding the limit), and sudden braking by some, cannot prevent collisions either at the site or elsewhere.

We have heard a lot on this website recently about effects of interventions that cannot be measured. The assumption often seems to be "it cannot be measured, but it's surely working". Well the data shows that speed cameras are not working and never have, which is consistent with my safety engineering assessment posted consistently here. It's the only outcome that makes any sense; if you don't address the causes of collisions, you'll not prevent them.
Eric Bridgstock, Independent Road Safety Researcher, St Albans

Agree (15) | Disagree (17)

Yawn...we've been here before and the penny still hasn't dropped. Neither the authorities nor the campaigners seem to realise that the effects of detection and prosecution of any motoring offences - not just speeding - can't be measured by simply trying to tie-in the site of the original offence to the accidents stats for that particular road. It doesn't work like that. Cameras are usually fixed so it's natural to assume they will have an effect where they are located and they may - or may not - but it's the behaviour of the offender post-prosecution and the decreased likelihood of accident involvement elsewhere that should be considered. That can't be measured however, so it gets overlooked.
Hugh Jones, Cheshire

Agree (14) | Disagree (11)

If you torture the data hard enough it will eventually tell you what you want to know.
Duncan MacKillop. No surprise - No accident.

Agree (11) | Disagree (17)