Petrol-heads twist the facts and treat it as a game, but real people die when these devices are turned off

The experiment is over and the results are in. In April, Thames Valley police switched Oxfordshire's speed cameras back on. They had been off for eight months, as a result of the government's decision to cut the road safety grant. Then the police began assessing the damage. In the 31 days before the cameras were switched off (July 2010), the machines caught 2,286 speeding motorists. In the 30 days after they were switched back on, they caught 5,917.

As many residents of the county complained, between July 2010 and April 2011, Oxfordshire became like a racetrack. The effect of the switch-off seems to have been felt far from the camera sites: as soon as motorists received the message that they were unlikely to get caught speeding anywhere in the county, they seem to have felt empowered to drive recklessly everywhere. Or so a more important set of figures might suggest.

In the eight months without cameras, there were 18 deaths on the roads in Oxfordshire, compared with 12 in the same period in the previous year. This was the first time in four years that the number of deaths on the county's roads had risen. Serious injuries rose from 160 to 179.

These are not just numbers: they are real people, some dead, and some who will have to live with devastating injuries for the rest of their lives. Reading the contents of websites that celebrate excessive speed, you would think it were just a game: evading the police, vandalising cameras and using clever lawyers to avoid getting fined. It's not. The consequences are real and horrible.

So far, the sample size is too small and the period too short to be sure that the deaths and injuries around the county are linked to the switch-off. The experiment would have to run for longer and be conducted over a wider area. Any volunteers?

Perversely, there are plenty. Undeterred by the results of Oxfordshire's grisly experiment, Staffordshire has now switched off almost half its cameras, for the same reason: a lack of funds, caused by the government's determination to end the mythical construct it calls "the war on the motorist". What it is really doing is allowing speeding motorists to conduct a war against everyone else: cyclists, pedestrians, children on their way to school, other drivers.

Worse still, the destruction of speed cameras by people who describe themselves as vigilantes continues unabated. Sixteen of Lincolnshire's 52 cameras, for example, have been destroyed by vandalism, in many cases by fire. In the Scottish borders, 19 have been burnt out since 2004. These acts are raucously celebrated on the boy racer sites.

Here's what a spokesman for the Lincolnshire Road Safety Partnership had to say about one of these burnings:

"That camera is protecting the standing traffic that mounts up at the A57 roundabout. At certain times of the day the traffic is backed up and people come down the hill at high speed and run on a bit. The idea of the speed camera is to slow them down so they can stop in time for the standing traffic that's ahead of them. And to burn that camera is just crazy - they're putting people's lives at risk by doing this."

So why are people burning cameras? Because journalists and others have promulgated a powerful and dangerous myth: that speed cameras are useless, and exist only to tax the public.

It doesn't matter how often or how comprehensively this myth is disproved. A study for the Department for Transport, involving more rigorous scientific methods than those deployed by Thames Valley police in Oxfordshire, shows that 19% fewer people were killed or seriously injured at accident black spots after speed cameras were introduced, above and beyond the general decline in accidents on the roads.

As for the stealth taxation story, the most recent figures I've seen, from 2010, suggest that the cameras cost slightly more to run than they make. The Treasury took £85-90m in revenues, with an outlay of £110m a year. This may have changed by now. (Why shouldn't reckless driving be taxed?).

Yet speed cameras are a much cheaper means of preventing speeding than any other. The Department for Transport reports a cost-benefit ratio of 2.7:1. The House of Commons transport committee found: "A more cost-effective measure for reducing speeds and casualties has yet to be introduced."

But never mind the facts: the tabloid myth is what the people who have been snapped by the cameras want to hear. Instead of being a danger to the public, they are, journalists tell them, innocent victims of a government mugging.

At times, the press coverage is so extreme that it amounts to blatant incitement. Here's what Jeremy Clarkson wrote in the Sun on 21 July 2007, under the headline "Speed cameras have been burned out by vandals":

As I drove down the M20 into Kent last Monday, I noticed that most of the speed cameras had been burned out by vandals. This is disgusting. It is ridiculous, criminal and stupid that the person who savaged these life-saving devices should target the M20 – and then stop. Why did you not keep right on going? I can think of six cameras on my way home that would be immeasurably improved with a spot of petrol and a match."

This looks like good clean fun, as Sarah Palin's placing of a gunsight over the state of Arizona did, until Gabrielle Giffords got shot. Incitement, particularly incitement that supports a false story that people want to hear, can have consequences.

More insidious than Clarkson's have been the efforts of Christopher Booker, who, through a grossly misleading use of statistics, has tried to suggest that speed cameras make the roads more dangerous.

I was reminded of this over the weekend, by Booker's pathetic attempt to justify yet another of his false claims in the Sunday Telegraph – I rounded up many of them in a blogpost last week. Uniquely, as far as I can tell, two articles of his have been the subject of long section of a high court judgement, which damned his journalism as "unbalanced, inaccurate and just plain wrong."

Like all propaganda that tells people what they want to hear, Booker's false claims are likely to change or reinforce people's behaviour. So are Clarkson's and those of all the other journalists who tell people that they can act as they wish, regardless of their impact on others. The rest of us have a duty to try to correct them.

monbiot.com