Gardaí have confirmed that more than 14,500 people who were prosecuted for road traffic offences are to have their convictions quashed.
Garda error is being blamed after some 14,700 people were prosecuted without a fixed-charge notice first being issued.
All those convictions must now be appealed and the State has to cover all costs, estimated to run into millions of euro.
The Assistant Commissioner in Charge of Policing Michael Finn has apologised to those who were wrongly convicted.
"It is our mistake and we will rectify the matter. The people involved do not have to take any corrective action until they hear from us," he said.
The announcement comes after Independent.ie last night revealed that figures posted on the official garda website about the number of breath tests carried out on drivers over three years were hugely exaggerated.
The wrong figures have been attributed to human error and flaws in the system of compiling and logging the numbers.
According to garda officers, the increase on the real figures ran into "thousands".
This morning it was revealed that from 2011 to 2016 the number of drink driving tests the gardaí claimed they had carried out was hugely exaggerated, by over 937,000, and was in reality far less.
Gardaí say they do not know why it happened and have pointed to system and policy failures, but also accepted it is reasonable for people to conclude many of the figures were just being made up.
The Policing Authority said it has repeatedly asked questions about possible wrongful prosecution and conviction of people who had already paid a fixed charged penalty, beginning in June 2016.
In a statement they said it was encouraging that this information has been put in the public domain.
"The Authority is alarmed at the scale of the discrepancies disclosed between actual alcohol tests administered and the numbers recorded by Gardaí."
The statement continues: "This is not just an academic statistical matter, it is an ethical one. It raises serious questions of integrity for the Garda Síochána organisation and combined with previous issues regarding inflated activity levels, erodes confidence in the credibility of Garda data generally.
"The gap between the Medical Bureau of Road Safety data of 1,058,157 tests administered and the Garda recorded data of 1,995,369 tests is close to one million and it raises a widespread concern in the way Gardaí go about their daily work. It again raises concerns about management and supervision, echoing findings of the Garda Inspectorate, Judge O’Higgins and others."
The Policing Authority said the scale of the discrepancy is "further evidence of deep cultural problems within the Garda service – a culture in which such behaviour was possible".
It called on the various arms of the State, the Director of Public Prosecutions, courts and gardaí, to work together to speedily remedy matters.
The statement continues: "These issues will continue to be pursued by the Authority as part of its oversight role."
Moyagh Murdock, chief executive of the Road Safety Authority, said she was greatly concerned as drink-driving is a factor in 29% of fatal crashes.
"There is a direct link between the levels of drink-driving enforcement conducted and compliance with drink-driving laws," she said.
"The absence of credible and reliable enforcement metrics such as the numbers of drivers being breath tested, makes it almost impossible to evaluate and measure the effectiveness of road safety interventions.
"This is especially valid in the context of the rise in road deaths over recent years."
Ms Murdock said the scandal may damage the public's faith in the ability of the Garda to effectively enforce life-saving road safety laws.
It is not the first time the Garda's record keeping has been called to account.
Last year, official analysis by the Central Statistics Office found almost a fifth of crime reported to the force was not recorded on its own system.
It also said the force's success rate in solving crimes is probably 10pc lower than claimed.
In 2015, the CSO said almost a fifth of crimes reported to the Garda in 2011 were not recorded on the Pulse database.
That followed a damning audit by the Garda Inspectorate, published in 2014, that exposed massive errors on the Pulse system including poor classification of incidents and under-reporting casting doubt on the country's true crime rates.
The watchdog concluded that it was difficult to determine the scale of unrecorded crime but it could be about a quarter of offences.