More than 200 senior Garda officers inappropriately - and in most cases corruptly - wiped penalty points from driving licences, new evidence handed to a powerful parliamentary watchdog claims.
In fresh allegations passed to TDs today, a serving whistleblower from within the force - a sergeant with around 30 years experience - also asserts that his life has been destroyed by the controversy.
"Having been treated the way I was for reporting the above. I don't think that I would do it again," he wrote to the Dail's Public Accounts Committee (PAC).
"It destroyed me, my career and my family."
Allegations of wrongdoing by senior gardai in operating the fixed penalty notice system have already been investigated by the auditor and comptroller general and internally by the force's assistant commissioner John O'Mahony.
Both reports were released last year.
But the PAC, which oversees the use of public money, plans to take evidence from two whistleblowers - one serving and one retired, John Wilson - on the claims next week in a move which has infuriated Garda Commissioner Martin Callinan.
Before the committee, Mr Callinan said he will take legal advice on what action is open to him ahead of the planned hearings.
The Garda chief also hinted at possible disciplinary action against the serving officer, who is now under supervision any time he wants to use the force's computerised record system Pulse.
Mr Callinan told the parliamentary watchdog that it was "fundamentally wrong" that classified information is being passed to TDs in an attempt to make unsubstantiated claims of wrongdoing.
"Frankly, I think it's quite disgusting, on a personal level I find it quite disgusting," he said.
"It is a strong term, it's my view," he agreed.
Mr Callinan said he did not want to suggest that he would take disciplinary action against the serving whistleblowers but warned he could not cede control of his rank and file.
"I can't in all fairness, I can't have a situation where members of An Garda Siochana are coming and making very serious allegations of a criminal nature and disciplinary nature and using a platform such as this committee to air their grievances without having a response," he said.
The Commissioner said he has not yet seen the allegations sent to the committee - which has since had personal details removed to protect identities of those involved in the alleged wrongdoing.
The committee has offered him the chance to see the material.
"These individuals have responsibilities as well, and making allegations that cannot be substantiated on regular basis is a particular difficulty that I may have to deal with," said Mr Callinan.
"I can not allow a situation to continue where information is being bandied around."
He said he has to seriously consider his own position and the position of the whistleblower over the controversy, and that he has been advised that both he and the whistleblower could be guilty of breaching data protection laws.
The country's most senior police officer said he needed to retain control of his own force and couldn't have thousands of officers investigating each other and making complaints outside internal processes.
There is a difference between exposing wrongdoing and leaking large volumes of information, he said.
But John McGuinness, committee chairman, said the watchdog had taken its own legal advice, and was assured the evidence - now redacted - was fully compliant with the Data Protection Act.
The Fianna Fail TD said the PAC had been handed new evidence from one of the whistleblowers ahead of today's hearing at Leinster House, in which it is alleged more than 200 senior garda officers terminated "fixed charge notices inappropriately and in most cases corruptly".