Motorists appear not to trust the way road taxes are levied by the Government, which MPs say has been inconsistent in how new charges are justified.
A report from the House of Commons Transport Committee said that road users are "an important source of revenue" but called for them to be treated "fairly and with openness".
The Government's phased increases to car tax charges were handled "so badly they tarnished the image of environmental taxes", committee chairman Louise Ellman, a Labour MP, said.
"Fuel duty has been presented, at different times, as a tool to reduce carbon emissions, a source of general revenue, and a means to fund transport investment," the committee report explained.
MPs said that "major issues" still had to be addressed over charges that hit drivers, including the fact that the Treasury's road tax policy does not link properly with the Department for Transport`s.
The committee also believes that parking tickets should not be used simply as a way of raising revenue.
The running costs of London's congestion charge use up almost half the revenue and if charges are introduced in other cities they must be administered differently, the MPs concluded.
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