Almost 15,000 people will have their penalty points quashed and fines repaid after a massive blunder in the way our roads are policed.
Senior Garda management has been plunged into a fresh crisis after the discovery of two major errors in road traffic policing. Gardaí admitted that 14,700 people were wrongly prosecuted.
They have also acknowledged that the number of roadside breath tests carried out over five years was grossly exaggerated in official figures.
The startling admissions drew an immediate rebuke from the force watchdog, the Policing Authority.
The first category of blunder involves 14,700 people convicted in the courts who were prosecuted without a fixed-charge notice first being issued.
Gardaí have now pledged to appeal those convictions to the circuit court to remove any penalties that were imposed.
The State will have to cover the costs of the process, potentially running to millions of euro.
Legal observers said the State could also be open to claims for damages, although the number of such cases was likely to be small as the quashing of penalties was expected to take the sting out of the issue.
Certain categories of motorists are more likely to consider legal action, including drivers whose insurance premium had increased significantly; those who have been disqualified after receiving 12 points and professional drivers who may have lost their job.
Read more: 'It raises serious questions of integrity' - Police watchdog condemn gardaí as over 14,500 traffic convictions to be quashed over error
It is also likely that the State would have to pay legal costs for motorists whose claims for damages were successful.
Separately there has been a major blunder in recording roadside breath tests.
The official figures, recorded on the force's Pulse computer and published on its website, showed there had been 1,995,369 roadside breath tests between 2011 and early 2016.
However data from the Medical Bureau of Road Safety confirmed that the real figure was 1,058,157 - a discrepancy of almost one million.
Gardaí said yesterday there was no one single reason, but suggested that the data had been collected in an era when they did not record the specific counter readings nor identify the device used in each test.
Over that period, more than 1,200 devices were in use across 108 Garda districts with no central recording process.
However, the Policing Authority said this was not just an academic, statistical matter - but an ethical one.
"It raises serious questions of integrity for An Garda Síochána and, combined with previous issues regarding inflated activity levels, erodes confidence in the credibility of Garda data generally.
"It again raises concerns about management and supervision, echoing findings of the Garda Inspectorate, Judge O'Higgins and others."
The Authority said it took the view that the scale of the discrepancy was further evidence of deep cultural problems.
Read more: Garda figures for number of breath tests carried out were 'hugely exaggerated'
Senior gardaí said they did not know why the exaggerations, which were first revealed by independent.ie on Wednesday night, had taken place - but thought it might have been due to system and policy failures.
But they accepted that it was reasonable for people to conclude that many of the figures had just been made up.
The Road Safety Authority will recommend the gathering of road traffic enforcement data should be independently audited and published regularly.
Meanwhile, Social Democrats co-leader Roisin Shortall said "heads should roll" over the latest Garda revelations.
Ms Shortall asked: "How many cock-ups does it take for senior gardaí to face accountability?"