GARDAI may investigate former Senator Ivor Callely over his use of allegedly fake invoices to make phone expenses claims.
It comes after the Standards In Public Office Commission (SIPO) referred the matter to the Director of Public Prosecutions (DPP).
The former senator claimed over €2,900 in expenses for mobile phones in November 2007 using invoices from a company that went out of business in 1994.
SIPO said it had formed the opinion that Mr Callely may have committed an offence relating to the performance of his functions as a member, and has forwarded its report to the DPP.
The DPP cannot prosecute on foot of a SIPO report, but it can ask garda to launch an investigation.
The Seanad members' interests committee had referred two complaints about the expenses claims to SIPO.
The commission appointed an inquiry officer to investigate the complaints on November 16 and the officer's report was considered by the commission at its meeting on April 11.
"Having considered the report, the standards commission formed the opinion that Senator Callely may have committed an offence relating to the performance of his functions as a member. Accordingly, it furnished a report in the matter to the Director of Public Prosecutions," it said.
As Mr Callely ceased to be a member of the Seanad on April 25, the commission no longer has jurisdiction in the matter and its investigation has been discontinued, it added.
Mr Callely, appointed to the Seanad by former Taoiseach Bertie Ahern in 2007, did not contest the current election.
The DPP will now look into Mr Callely's claim for €2,907 to cover mobile phone handsets and car kits allegedly bought from a company called Business Communications Limited between 2002 and 2005.
The claims refer to a time when Mr Callely was a junior minister.
In a statement last year, Mr Callely accepted he should not have made the expenses claims but added that he did not know how the receipts were issued by a company that had ceased trading.
Mr Callely's political career has been dogged by controversy.
He was forced to step down as a junior minister in 2005 after it emerged his home had been decorated for free by a construction company in the 1980s. He was also the focus of controversy last year when it was revealed that he was using west Cork as his home address, claiming large overnight and travel expenses.