HUNDREDS of gardaí were involved in widespread exploitation of the penalty point system which saw them wipe fines and points for friends and relatives.
The Garda Ombudsman found one officer cancelled 744 fixed charge notices across 17 counties during the four years it examined.
The watchdog warned that superintendents and inspectors wiped points and fines for driving offences outside their geographical area, contrary to policy.
Almost three quarters of the records of notices being cancelled did not carry any sufficient rationale for the action.
Some 442 officers were authorised to wipe fixed charge notices in the four years from 2009 to 2012, the report found.
The Garda Ombudsman also found that some serving gardaí used the credentials of retired senior colleagues, who would have had the authority to cancel the penalties, in order to wipe the slate clean for friends and relatives.
The report is the latest in a long line of reviews of the scandal that was exposed by whistleblower Sergeant Maurice McCabe.
At the height of inquiries into his allegations at the public accounts committee former Garda commissioner Martin Callinan described the claims as "disgusting" while Taoiseach Leo Varadkar, then transport minister, said Mr McCabe was "distinguished".
The Garda Síochána Ombudsman Commission (Gsoc) said it received data relating to the issuing of 1.6 million fixed charge notices and 74,373 cancellations of these penalties and fines over the four years under examination.
The watchdog met Mr McCabe five times during its investigation.
Gsoc said it also examined previous reports on the controversy, including the internal report by Assistant Commissioner John O'Mahoney, the review of revenue issues by the comptroller and auditor general and the Garda Síochána Inspectorate. All identified systemic failures.
Gsoc said it will not be investigating individual officers for potential criminality or disciplinary issues as the bill for that has been estimated to run to more than a million euro.
"The Ombudsman Commission believes that the considerable cost to the public of continuing our investigation into a second phase – of investigating specific cancellations instances with a view to identifying possible behaviour of a criminal nature or constituting a breach of discipline – would outweigh the benefit," the watchdog said.
There is also a significant risk for overspend, Gsoc said.
The watchdog also warned its work would be hampered by a lack of supporting documentation for large portions of the cancellations.
It said there is no possibility of recovering fines or otherwise sanctioning motorists who may have had fixed charge notices cancelled improperly.
Gsoc also said there is no guarantee that gardaí would be prosecuted or disciplined.
In a letter to Acting Garda Commissioner Dónall Ó Cualáin, Gsoc said: "While we are ending this investigation, our interest in road safety and public confidence in garda behaviour in this area means we will keep complaints of infringements of this nature to the forefront with the hope that such complaints will become infrequent as better internal oversight deals with the legacy of poor practices in the past."
The report said too many members of the Garda were authorised to cancel the notices.
It noted a "sizeable" volume of cancellations with no reason or supporting documentation.
The scrapping of notices issued to garda members, notably for speeding offences, was undertaken without any checks to establish that the garda was on duty at the time and that exceeding the speed limit was necessary, the report said.
There were multiple cancellations for the same people and the same vehicles, with no apparent checks undertaken beforehand.
Superintendents used "discretion" to cancel FCNs without any consultation with the Garda member or traffic warden who issued it, the review added.
It concluded: "The data considered in this investigation allows Gsoc to be satisfied that the allegations made by Sergeant Maurice McCabe in relation to the operation of the Fixed Charge Processing System were merited."
In a statement the Garda said it recognised the system had systematic flaws and some members were using it inappropriately.
It thanked Mr McCabe for his valuable role in reforming the system and said measures had been introduced to ensure such issues could not arise again.
"An Garda Síochána welcomes Gsoc's finding that the 'procedures for dealing with fixed charge notice cancellations have dramatically changed in recent years'.
"The Gsoc report notes that the number of Garda members with the authority to cancel notices has reduced to only three people.
"In addition, the Gsoc report finds that the former president of the Circuit Court, Mr Justice Matthew Deery, who has since January 2015 acted as the oversight authority for the fixed charge processing system, has conducted two audits of the system and 'has reported substantial compliance with the revised policy'."
It highlighted that all cases involving Garda members seeking to have fixed notices cancelled on the basis of performing official duties in their own vehicles are now referred to the office of the DPP for independent determination.
"An Garda Síochána will continue to closely monitor compliance with the revised policies and procedures relating to the fixed charge processing system to ensure the high levels of compliance are maintained and there is public confidence in the system," it said.
