Thousands of motorists could be spared bans under Tory plans to axe penalty points for many speeding offences.
Most drivers caught by speed cameras "should not get points"
Shadow transport secretary Damian Green said many drivers caught by speed cameras should face only fines, not points on their licences.
But stricter penalties - such as four or five points and higher fines - would be given for speeding in more dangerous areas, such as outside schools.
Motoring organisation the AA warned the plan would send out "mixed messages".
Drivers risk losing their licences if they reach 12 penalty points, a limit which can currently be reached with only four offences.
An estimated two million people received £60 fines and three penalty points in the last year, according to police chiefs.
Many of these were caught by Britain's 4,500 speed cameras.
But Mr Green said only about 1,000 areas, where the risk of death was highest, should carry penalty points.
He also called for an audit of the country's cameras, to find out which ones actually reduced road accidents and which appeared to be there just to raise money.
"Many motorists are very suspicious that too many of the cameras are there to raise money, rather than to make our roads safer", Mr Green told BBC News.
Most of the money from fines pays for administering the system, but Mr Green said the Treasury creamed off the rest - up to £20m.
He suggested "all money raised by speed camera fines should go back into road safety" to restore confidence in the system.
Mr Green said the current system undermined faith in the way road safety was being enforced.
He said: "The danger is that millions of people are starting to think that the law is being imposed in an arbitrary way."
Andrew Howard, from the AA, said he was "puzzled by the proposals", which sent mixed messages to motorists.
He asked how drivers would know if they were on a lower penalty "safe" road or a high penalty "unsafe road".
"It would be much better if you made the entire system much more transparent to let people understand why the cameras are where they are but leave the penalties is there now," he said.
Mr Howard said he did not consider the current laws to be unduly harsh: "If you
receive four speeding fines in three years, I don't think many people would
think you were unfortunate (to earn 12 points and lose your licence)."
Liberal Democrat peer Baroness Scott, from the Local Government Association's transport executive, said speed limits should be changed, not penalties.
Speed cameras are only supposed to be used on blackspots where they have been four accidents and evidence of speeding.
Transport Minister Tony McNulty said the government was writing to all councils and police forces to ensure those guidelines were met.
It would then decide whether to force them to take down any cameras be used to raise money rather than as a road safety measure.
Mr McNulty said the government would look to see if there was any merit in the Tory ideas.
Dismissing fears road safety would be undermined, Mr Green said the Tories would target the most dangerous areas, particularly those used by many pedestrians and children.
Taking 10mph off the speed limit in those areas and increasing the penalties for speeding would do a great deal to help, he claimed.
"Drivers would know that in those particularly dangerous areas they absolutely shouldn't even think about speeding beyond what would be a lower limit."
A Conservative Central Office spokesman said the party intended to consult on its plans.