Developer turned politician Mick Wallace claimed taxpayer-funded expenses for payments to his own restaurant chain.
Mr Wallace, an independent TD for Wexford, paid €5,780 last year to Wallace Calcio - a company he set up in 2003 to run bars, cafés and restaurants. He remains a 40pc shareholder of the company.
According to documents with the Standards in Public Office (Sipo), Mr Wallace claimed back expenses for amounts paid to the company for "meetings etc".
He claimed the expenses under the Parliamentary Activities Allowance (PAA).
The allowance was established to allow public representatives to pay for research, public relations and polling.
"The allowance is payable in relation to expenses arising from parliamentary activities, including research, of that member," according to Sipo.
The body, which is responsible for ethics in public office, also advised the PAA can be spent on entertainment - however, TDs and senators should remain prudent in this spending.
"The commission would suggest that independent members should be conscious of the need for strict economy for expenditure on entertainment which should only be incurred when there is a clear business need.
"Records should be kept of the nature of the business and the persons availing of the hospitality (including members themselves)," Sipo's guidelines said.
The annual allowance payable under the PAA to independent members of Dáil Éireann is €37,037 or €21,045 for members of the Seanad.
The allowance is not subject to income tax.
While no receipts need to be provided for payment of the allowance, TDs and senators must provide a detailed breakdown which must be audited by an independent accountant.
Company records show that Mr Wallace resigned as a director of Wallace Calcio in March this year.
At the same time, his son Fionn Wallace was appointed as a director.
The Sipo records also showed Mr Wallace claimed expenses under the PAA for work undertaken by this son.
He paid more than €20,000 to Fionn Wallace for "research" and "policy formation", according to a report in 'The Sunday Times'.
It said the only other claim made from the PAA expenses last year by Mr Wallace was for €6,610.
This was for "technical or specialist advice likely to be required in connection with legislative proposals or potential parliamentary initiatives".
Calls to Mr Wallace for comment were not returned last night. However, he took to Twitter where he claimed the facts of the story were misrepresented.
Mr Wallace hit headlines last week when his abortion bill on fatal foetal abnormalities split the Cabinet. The three Independent Alliance ministers Shane Ross, John Halligan and Finian McGrath, voted against the Government and for the bill. However, the bill failed to pass the overall Dáil vote.