The findings also show that politicians and civil servants have indirect incentives to clock up mileages thanks to generous reimbursement rates.
Lord Privy Seal, Lord Williams of Mostyn, has disclosed that mileage allowances for members of the Houses of Commons and Lords differ from those offered to members of the Scottish Parliament and Welsh Assembly.
For example, a member of the Welsh Assembly is reimbursed at a rate of 45 pence per mile for the first 20,000 miles and then 25ppm thereafter, while a colleague in the Scottish Executive can claim all business miles at 49.3ppm. Reimbursement rates for a member of the Houses of Commons and Lords is 53.7ppm for the first 20,000 miles and 24.8ppm thereafter. The approach of departments to alternative transport also differs drastically.
Fleet consultant Stewart Whyte, managing director of Fleet Audits, lambasted the Government's approach.
He said: 'By setting such high rates, the Government is doing nothing to set an example to industry and other public sector bodies to control their transport expenditure. 'The rates undoubtedly carry a profit element and therefore subject politicians to the same perverse incentive of clocking up business miles which the Government claims fleets have.'