Cornwall county councillors, who are paid 50p a mile for driving their own cars to meetings, may be overclaiming thousands of pounds a year more than they are entitled to, a Packet investigation has revealed.

Using the Freedom of Information Act, the Packet has acquired copies of expenses claim forms submitted by the 82 county councillors over a three-month period last year and these have been analysed by comparing them to AA and RAC mileage data.

The investigation reveals that many councillors are claiming they have travelled more miles than the shortest route mapped for the Packet by either the AA or RAC. If the AA and RAC data is correct, figures for one month alone show that councillors claimed for up to 1,700 miles that they did not travel.

This would have added £853 to the expenses bill of £13,000 for just the one month that the Packet audited. If the figures for this one month are projected over a full year, county councillors are being paid about £156,000 a year in mileage expenses and could be overclaiming by as much as £10,000.

The 50p a mile payments that councillors receive for using their own cars have already been criticised as being over-generous. Last year an unsuccessful attempt was made by some councillors to reduce the mileage rate. They pointed out that motoring organisations say that an average car costs around 38p a mile to run and councillors are therefore making a profit every time they drive to a meeting.

The request to reduce mileage rates prompted a full review of the allowances and expenses paid to councillors. But, instead of producing a saving for Cornwall's taxpayers, the council eventually voted to double the allowances paid to senior members, adding £160,000 a year to costs. The mileage allowance was left untouched at 50p. The expenses claim forms seen by the Packet reveal that David Whalley, leader of the Liberal-Democrat controlled council, claimed for travelling more than 6,000 miles over a three-month period last year.

This means he would have picked up expenses of about £1,000 a month on top of his annual allowance of £19,305 - due to be increased to £32,655 later this year.

The retired head teacher - who receives a local government pension as well as his publicly-funded council allowances and expenses - travels from Bude to attend meetings at County Hall in Truro. He claims 108 miles for each round trip. Using the mileage databases of the AA and RAC the Packet calculated that the shortest distance between Mr Whalley's home and County Hall is only 104 miles, which - if correct - would give him an additional £2 profit on every one of the numerous trips he makes as council leader.

In the one month that the Packet analysed in depth, Mr Whalley also claimed 130 miles for travelling to a meeting at the Tremough university campus in Penryn. The shortest journey between his home and Tremough, according to both the AA and RAC, is a round trip of only 120 miles, giving him an additional £5 over and above the £60 the motoring organisations suggest he should have received.

Mr Whalley also claimed 141 miles for attending a meeting in Hayle - nine miles more than AA and RAC databases give as the distance.

There is no suggestion that Mr Whalley - or any of the other councillors - are deliberately cheating local taxpayers. The mileages they are claiming could be as shown on their own car odometers and the AA and RAC databases could be at fault. It is also possible that they have taken a longer route to avoid traffic or that they have simply made a genuine mistake calculating the mileage.

The findings, however, are likely to prompt calls for a full audit by a government accountant to make sure councillors are not receiving more than they are entitled to.

Besides Mr Whalley, a number of other Liberal Democrat councillors have also claimed for journeys that reveal a greater mileage than shown on the AA and RAC databases.

Bob Emuss claims 90 miles for the round trip between his home at St Cleer, near Liskeard, and County Hall. According to the AA and RAC, the round trip would be 77 miles taking the fastest route but only 71 miles following the shortest route. Assuming that the AA and RAC figures are accurate, he would have been overpaid £95 in one month alone based on the lower mileage.

Adam Paynter, a Liberal Democrat councillor from North Petherwin, near Launceston, was overpaid by £83 in the same month based on the AA and RAC figures. He regularly claims 112 miles for the round trip from his home to County Hall but the shortest route, according to the motoring organisations, is 98 miles. He also appears to have overclaimed for official journeys to Scorrier, Penryn and Gwithian.

Other Liberal Democrat councillors who appear to have claimed more in the one month examined by the Packet than the shortest distance shown by the AA or RAC are: Saltash councillor Mrs Joyce Mepsted, 105 miles; Brian Higman, Roche, 101 miles; Paul Adams, Pelynt, 91 miles; Robert Booker, Week St Mary, 70 miles; Mrs T Lello, Hayle, 71 miles; Andrew Mitchell, St Ives, 59 miles; Bryan Preston, Saltash, 55 miles.

An independent councillor, Tony Nettle. from Callington, claimed 104 miles for each round trip from home to County Hall compared to the AA and RAC mileage of 86, giving a possible over-payment of £45 for the month. Another independent, Neil Burden, from Trebullett, near Launceston, may have overclaimed £44 for the month if the AA and RAC figures are accurate.

Some councillors appear not to have claimed any expenses at all for the month examined in detail by the Packet and many others have claimed almost exactly the mileages shown on the AA and RAC databases. A few have actually claimed less than the distances shown for their journeys on the AA and RAC databases.

Council leader David Whalley told the Packet that he had always claimed 108 miles for the round trip from his home in Bude to County Hall in Truro.

"When I checked it out I found that I actually do 110 miles from my home to County Hall so I have been underclaiming as I still claim 108 miles," he said.

"I set my speedometer for journeys that are irregular. For regular ones to County Hall in Truro I have always used the 108 since I first started. Since then I have found out it is more than I claim."

Mr Whalley added: "To be honest, there have also been occasions when I have gone a longer distance than I would normally do and have put in the normal claim. For example, on the day of the Boscastle disaster it took me seven hours to get home and do 50 to 60 miles further than the normal 108 miles."

Coun Andrew Mitchell said: "I totally dispute the claim that I overcharge. I claim mileage from when I leave my front door to when I get to County Hall. If anything I underclaim.

"If you want to come in the car with me and see what is on my speedometer you are more than welcome. I have no problem with that."

Coun Robert Booker said that often distances on a map were different than the actual distances travelled due to the terrain negotiated in transit.

"It can also make a difference if you have brand new tyres on your car or worn tyres, because of the difference in their diameter. But if, as you say, I have claimed for something which I haven't had then I would like to know."

Coun Bob Emuss said that the reason he was overclaiming was because he was travelling the quickest route to County Hall which took him via Shortlanesend after dropping off his daughter at Liskeard. "The finance officer has picked up on this and I now go the shortest route which means I get stuck in traffic up in Tregolls Road every day. It means I have to leave home much earlier."

Coun Joyce Mepsted said: "The database is just taking a point, I would assume, on a map, from point A to B. What I claim for is the mileage I drive when I get in the car at Saltash and when I get out of the car at County Hall. The RAC haven't got in my car and driven. That's what I do. I claim for what I actually drive - when I get in the car and again going back."

Coun Adam Paynter said: "The quickest route to go from my house, as I live in the middle of nowhere, is to go through a lot of back roads to the A39 to go along the north coast road. That would take about 20 minutes longer than going the quickest route, through Launceston.

"The official claim for members that we have in our handbook for councillors is 98 miles from Launceston to County Hall. I'm seven miles away from Launceston and it takes just over an hour going that way. Although it as a few miles more than the shortest route it would end up taking about 20 minutes longer each way. I just work out what my mileage is on my car and claim that."

Coun Paynter said he also tended to avoid using the A30 in the summer because of the heavy traffic.

The Packet has tried to speak to other councillors whose claims are more than the AA or RAC distances but it has not been possible to contact them all.

For a full report with further comment see this week's Packet.