Speed cameras have been criticised
Campaigners for road safety are demanding that the government press ahead with plans to introduce thousands more speed cameras, paid for by speeding fines.
Ministers are considering the move, following a series of speed camera funding trials which succeeded in reducing road casualties.
But they are worried at signs of growing opposition to the number of cameras on the roadside.
One police force has already announced that it will not be going ahead with any general expansion of speed cameras, for fear of alienating the public.
Speeding 'endemic'
The proposals follow trials involving eight police forces. They all resulted in fewer casualties, but also far more speeding fines.
In Northamptonshire, deaths and serious injuries fell 14%. But the number of speeding tickets went up from 4,000 to 84,000 a year.
A survey for the road safety group Brake suggests motorists are split.
Some 70% of those asked believe cameras do save lives but 44% think there are enough cameras. And only 7% think fines should be used to buy more cameras.
Government figures show speeding is endemic among car drivers, with more than half breaking the law on motorways and on 30mph urban roads.
Hidden
But ministers are worried that increasing the number of cameras could lead to falling public support.
Some drivers believe police are hiding cameras, or using them to raise revenue, even though guidelines say cameras should not be hidden, and prevent police from making a profit.
They may need to strengthen the guidelines, to keep public opinion on side.
In London, which has over 3,000 cameras, the Metropolitan Police has announced there will be no further general expansion, for fear of alienating the public.
From now on, new cameras will only be placed at accident blackspots.
The government is expected to announce whether to will press ahead with the plans for more cameras later this month.