Motoring campaign groups have attacked a "revenue-raising" temporary speed camera which has brought in over £1m in fines during the past 18 months.
The camera caught 18,000 motorists driving too fast
The Gatso camera at roadworks on the M62 at Ferrybridge raised £1,088,000 from 18,000 drivers.
The RAC Foundation said the camera was obviously not deterring motorists from speeding and the issue seemed to be more about revenue than safety.
The Highways Agency said it used cameras where necessary for safety.
But Edmund King, Executive Director of the RAC Foundation, said he doubted safety was the main aim of the camera.
He said: "The camera's objective should have been to slow people down.
"It is obvious it was not doing its job by the number of motorists speeding.
"It raises the issue of whether this is more about revenue-raising than safety."
The motorists caught by the camera also forfeited some 50,000 penalty points on their driving licences.
Paul Smith, of the Safe Speed road safety campaign, said speed cameras could increase danger because they could alter driver behaviour.
He said: "They cause traffic to bunch and some drivers to panic brake. They also cause excessive concentration on the speedo at the expense of concentration on the road ahead.
"But speed cameras also undermine our road safety system in subtler ways.
"They damage the police-public relationship and imply a series of false safety messages.
"The Highways Agency is ignoring the science and apparently prefers blind and unjustified faith in speed cameras."
Philip Gwynne from the West Yorkshire Casualty Reduction Partnership said: "Anybody who feels that the cameras are just there to raise revenue has the power in their own hands to stop it happening.
"You just don't speed. Then you can't get a speeding ticket and they can't raise revenue and we can all pack up and go home."
The Highways Agency said it was "appropriate" to use cameras to enforce speed limits and protect roadworkers.
Five were killed and 12 were seriously injured in the course of their work on England's motorways and major A roads, the agency added.
A spokesperson said: "Safety cameras help reduce the risks faced by the workforce as they carry out their difficult work.
"The Highways Agency and its contractors ask drivers to help us stop the death toll rising by driving with care and consideration, and in particular to slow down near roadworks."