Just over one in 20 drink drivers are detected, an analysis of official figures indicates.
A survey of motorists in Ireland found 284,000 admitted to having an alcoholic drink before driving over the past year, gardaí said.
Some 40% of self-confessed drink-drivers who were polled for the study owned up to having had two or more drinks before getting behind the wheel, road safety chiefs revealed.
This suggests 113,600 motorists drove during the year while twice the legal limit.
Preliminary enforcement figures released by gardaí reveal fewer than 6,000 people were arrested on suspicion of driving while intoxicated between January and October. This equates of to an annual rate of 7,200 drivers.
Source: Brian Hutton, Irish Examiner, 27/11/15