The audit said 23% of these expenses did not have supporting receipts and of the 77% which did 32% only had credit card slips instead of detailed breakdowns.
The auditors, Kealy Mehigan, looked at €111,865 incurred by its 43 full-time and 35 temporary staff over a 10-month period in 2008. Mr Clarke’s credit card accounted for €61,546 of this and a further €5,278 arose from other travel expenses from his work.
His expenses were approved and initialled by chairman of the INS, Chryss O’Reilly, and the auditors recommended a number of changes to the regime.
It said full suppliers’ receipts should be kept to verify credit card bills, diaries should be kept by key personnel detailing the purpose of trips and these should be checked by whoever approved the expenses.
The INS has told Agriculture Minister Brendan Smith it has revised its travel policy. Its annual report for 2008 had acknowledged it had probed internal controls and had acted on it.
The most expensive trip during the period was the Royal Ascot festival in June.
Three rooms at the five-star Pennyhill Park for Mr Clarke, stallions nominations manager Julie Lynch and former director Pat O’Kelly cost €9,653.
A further €2,433 was incurred by Mr Clarke in non-accommodation expenses; €886.39 on drinks at the race track, €1,649 on chauffeur services and €182.54 on hotel tips.
Revelations regarding the level of expenses at the INS has provoked criticism by the Public Accounts Committee, which has demanded a report from the Department of Agriculture.
However, both the INS and Agriculture Minister Brendan Smith said Mr Clarke’s expenses were in keeping with his role and international travel was integral to his work.
The auditors also raised issues with the purchase of €1,404 in shrubs for the patio at Mr Clarke’s home at Tully House. Their report said there was no receipt and they should not have been listed as a travel expense.
When Mr Clarke was chief executive the INS paid for his home and upkeep expenses at Tully House, including €22,258 for a new patio. Separate to his travel expenses Mr Clarke was reimbursed for four months’ hire of a Volvo V70 after his company car was crashed.
The auditors also looked at Ms Lynch’s bills. She accounted for 15% of the company’s travel expenses. Her bill came to €19,933 over the period, including €660 to replace a television in her company-provided house.
The remainder of the staff expenses were largely mileage claims.
The details of directors’ expenses at the INS, between 2001 and 2009, were also released under the Freedom of Information Act. These came to €85,397. The bulk of the bill (€71,157) was built up by former director Pat O’Kelly.
She was nominated by the board to help identify international mares and stallions for purchase by the INS.
Mr Clarke retired from the INS in January. He was contacted yesterday but did not comment.