SPEED cameras are a regular sight on British roads, and thousands more are planned.

Precisely why, no one seems certain.

Some argue that such a visible threat of a fine is bound to result in fewer cases of speeding and, as a result, fewer deaths and injuries.

That sounds a logical stance. When we see a speed camera, along with those white markings on the road, we make sure we're not breaking the speed limit.

Britain has the best road-safety record in Europe, apart from Sweden. When there were only two million vehicles in Britain, they killed more people every year than our 27 million vehicles do today. On average, almost 10 people are killed every day on our roads.

The Government is convinced that speed is a major factor in road accidents. One senior road traffic engineer says: "Speed is a factor in more than a third of all road collisions.

"A vehicle hitting a pedestrian at 35mph is eight times more likely to kill than at 30mph."

Our MPs are on the case. The House of Commons Transport Committee has stated that "too little" has been done to cut down on speed-induced road accidents. The Committee speaks of the 'slow progress' of Govern-ment policy on road traffic speed, and called for speed cameras to cover the entire country by 2004.

"The Government has to give leadership," said the Committee. "It needs to make it very clear that speeding is unacceptable."

You can see that this viewpoint adds to the authorities' enthusiasm for speed cameras.

Yet last year, when lots of the cameras had already been brought into use, the number of deaths among car users rose by 5 per cent, though the overall increase for all road users was by only around 1 per cent.

Nevertheless, this means that 34 additional families were plunged into tragedy by the loss of a loved one.

Over the past decade road deaths have fallen significantly from 4,568 in 1991 to 3,443 in 2001.

Yet one county has seen road deaths rise by 17 per cent, and in one city deaths increased from 46 to 55.

Do those figures suggest that speed cameras are effective?

If the aim is to deter speeding, why do councils sometimes position cameras where they cannot be easily spotted?

Through a series of contradictory announcements, motorists have been led to believe that all cameras would be made more visible, warning signs would be made more obvious, and that cameras would be positioned only in proven accident blackspots.

Most cameras are painted a dull grey, though a few are bright yellow. This not only increases the motorist's chance of noticing them, but also ironically allows the local authority to keep a percentage of the revenue.

The Association of British Drivers feels that cameras and speed-checking systems are used as a way of raising money for police forces, rather than a way of persuading motorists to drive more slowly.

It points out that in various parts of the country, cameras have been hidden behind signs or bushes, or have been sited on roads with no history of accidents.

The ABD says the casualty figures prove that the Government's 'Speed kills' campaign is failing to tackle the real road-safety issues. While the Government has been "raking in cash" from speed cameras, our roads haven't got any safer. "Instead, they have grown more dangerous."

The ABD an all-round lobbying group for "the beleaguered British motorist, reclaiming the roads for the people who pay for them" wants the Government to switch its emphasis away from revenue-gathering to genuine road safety improvements.

ABD spokesman Ben Lovejoy says the focus should be on educating road users, instead of "breeding a generation of drivers who are scared to look up from their speedometers to see what is happening in front and behind them.

"It is far more important that they look ahead to see the child running towards the road, than look down to see whether they are doing 30 or 35mph."

In some areas, cameras are placed at points where drivers suddenly see them as they reach the top of a hill. Skid marks on the road show that the speed cameras create additional danger as drivers stamp on their brakes.

Some drivers, of course, are a danger to everyone. They ignore the logic of getting in the right lane, and hog the overtaking lane at ridiculously low speeds, thus annoying other drivers. Others are seen using their mobile phones when they should be concentrating on the potential dangers around them.

On motorways you find drivers who will not slow down, even for just a few seconds, in order to queue in the 'slow lane' for the exit sliproad, but instead leave it to the last moment to push in late, as near to the junction as possible.

No one is really perfect. Lorry drivers are probably the most capable of road users, yet too often they drive like bad-tempered bullies and 'use their weight', with deadly results.

The bottom line, which most of us would accept if we are honest, is that any reasonable and safe tactic should be acceptable if it saves lives.