Cheques totalling £15,084.44 were paid to Le Coq Hardi restaurant in Dublin from the Fianna Fail leader's allowance account in 1991, the tribunal was told.
The five cheques, which were co-signed by Mr Charles Haughey and Mr Bertie Ahern, include two payments of £4,532.81 and £4,106.08.
Counsel for the tribunal, Mr Jerry Healy SC, said the cheques paid to the restaurant in a nine-month period "required some explanation".
"A question arises how, in the ordinary way, such a large sum of money came to be written out of the account in favour of one restaurant," he said.
Mr Healy displayed copies of 11 cheques drawn on the leader's allowance account in AIB's Baggot Street branch, Dublin, mainly in 1991. The amounts added up to more than £30,000.
By examining the operation of the account in that year, the tribunal may be able to form some impression of how it was operated in other years, he said. The eleven cheques were:
A £2,403 cheque payable to Adare Manor hotel, Co Limerick, dated December 20th, 1990. Mr Healy said the tribunal wished to establish how the cheque was signed or co-signed and what information both signatories had about its purpose.
A £3,183.95 cheque payable to Celtic Helicopters, dated February 21st, 1991. Celtic Helicopters had told the tribunal that this was block payment for flying hours, Mr Healy said.
A £4,532.81 cheque payable to Le Coq Hardi, dated April 4th, 1991.
A £4,570.49 cheque payable to AIB, dated May 15th, 1991. Mr Healy said it seemed likely that this was a payment for some sort of bank draft or cheque.
A £4,106.08 cheque payable to Le Coq Hardi, dated June 28th, 1991.
A £2,000 cheque payable to AIB, dated July 31st, 1991. Mr Healy said this was a round sum cheque and previous evidence was given about a significant number of round sum cheques, some of them in extremely large amounts, which the tribunal had not been able to obtain any information about.
A £2,027.94 cheque payable to Le Coq Hardi, dated September 26th, 1991.
A £2,726 cheque payable to Celtic Helicopters, dated October 27th, 1991. Mr Healy said the tribunal had been informed that this too was in respect of flying hours.
A £1,757 cheque made payable to Le Coq Hardi, dated October 29th, 1991.
A £1,000 cheque made payable to cash.
A £2,660.29 cheque made payable to Le Coq Hardi, dated December 17th, 1991.
Mr Healy said a cheque for £25,000 payable to cash and drawn on the leader's allowance account, dated June 16th, 1989 was lodged to an account of Amiens Investments in Guinness & Mahon bank.
The tribunal noticed this while it was examining accounts in Guinness & Mahon under the control of the late Mr Des Traynor. He said the tribunal was unable to obtain any information concerning this cheque, and felt it appropriate to examine the leader's allowance account the cheque came from.