Wexford deputy Mick Wallace was one of five parliamentarians who had to refund expenses because he could not produce receipts or relevant documentation justifying his claim.
Deputy Wallace, who had to repay €860, was the one of the five parliamentarians who had to refund money who is not a new TD or senator.
The other four were Fianna Fáil TD Niamh Smyth, who had to repay €6,881; Fine Gael TD Maria Bailey, who returned €149; and Sinn Fein senators Pádraig Mac Lochlainn, who repaid €1,232 and Rose Conway-Walsh, who repaid €1,834.
The remainder of the 22 politicians audited in 2016 were able to justify their expenses under the Parliamentary Representation Allowance.
In its report accountancy firm Mazars said that Deputy Wallace had shown receipts or relevant documentation for €16,238.28 which was paid to him during the period of the audit. It found he was 'unable to show relevant documentation, within allowable expenditure categories' in respect of €860.64 claimed by him during the period under audit.
In total the expenses returned by the five elected representatives amounted to €10,956. Of this €3,882 related to spending on advertising or sponsorship; €2,639 related to out-of-date expenses; €2,752 fell into categories deemed "not allowable"; and no receipts or documentation could be produced to support another €1,683.
All five politicians refunded the ineligible expenditure within two months.
Mazars carries out an annual audit of expenses of a randomly selected group of TDs and senators on behalf of the Oireachtas. The audit was in respect of the period February 26, 2016 to December 31, 2016.
The report accompanying the audit said that the definition of advertising expenditure had caused confusion among some members of the Oireachtas. Some TDs and senators had claimed the full cost of newspaper advertisements, even though they were shared with another politician, for example a local councillor. Mazars recommended that the Oireachtas clarify that members should split the cost of the advertisement with other parties.