Central Bank of Ireland bosses are to face questions about whether they considered reporting the Davy controversy to gardai.
Representatives will appear before the Oireachtas Finance Committee to give evidence on how the bank handled the investigation into the stockbroker.
The regulator will also face questions about the €4.1 million fine it issued Davy for breaches of financial market rules.
Labour TD Ged Nash said the Davy scandal was motivated "by greed".
On Monday, Davy said it had closed its bond desk following the fallout over its fine for breaching rules in relation to a bond deal in 2014.
Mr Nash said the Central Bank needs to answer why the investigation into the incident took a number of years.
"It took seven years from this transaction when it first took place, and five years from the conclusion of a High Court case, for the Central Bank to come to the conclusion that wrongdoing took place in relation to the Davy transaction," he said.
"There are also many questions for Davy as well.
"It's quite extraordinary for people, looking in on the evolution of the scandal, as to why most of those who were involved in this egregious transaction, why they still clung on to their jobs for seven years.
"I have serious questions to ask of the Central Bank about their conduct of this investigation in the finance committee."
He went on: "One key question for me will be, has the organisation taken their responsibility seriously, and have they fulfilled their obligation, where they view the possibility of a fraud or deception has taken place, to actually provide An Garda Siochana and the Office of the Director of Enforcement with information that they would require in order to investigate matters of this nature?
"That's a very significant issue.
"The question is how has the Central Bank fulfilled its obligation in that regard?
"People want individuals to be held to account for their actions; that is the least that the Irish people are entitled to expect."
On Monday, the National Treasury Management Agency (NTMA) withdrew Davy's authority to act as primary dealer in Irish Government debt.
The NTMA described the firm's behaviour as falling substantially short of the standards expected.
Co-leader of the Social Democrats Catherine Murphy said she asked Taoiseach Micheal Martin and Finance Minister Paschal Donohoe whether they are considering escalating the issue to the Garda Crime Bureau.
"The finance committee will be discussing some of this today, and we have a letter sent to the Central Bank in relation to a range of questions that need to be responded to," Ms Murphy added.
"It's not surprising there is a public interest in this because the public are fed up with this kind of type of non-compliance, breaking of the law that is happening in the financial services that emerges from time to time, and it's very clear that there's a lack of consequences."
