The first proper estimation of the scale of non-reporting of crime has emerged in the findings of a survey of crime and victimisation compiled by the Central Statistics Office.
When asked why they did not report such seemingly serious offences as burglary, theft from vehicles and assaults, some 30 per cent of respondents replied that they believed the Garda would not or could not do anything.
Almost 40 per cent of people who said they had suffered theft with violence said they did not make a report to the Garda.
The extent of the non-reporting of crime emerged in a questionnaire on crime and victimisation included in the Quarterly National Household Survey, the most authentic and extensive survey carried out by the State. Some 39,000 households are questioned annually for the CSO survey.
Altogether the report records some 280,500 crimes of burglary, car theft, theft from cars, vandalism, personal thefts and assaults.
According to the CSO statistics 160,464, or about 45 per cent, of these crimes were not reported to the Garda.
Between September and November last year respondents were questioned about crimes against themselves and their households over the previous 12 months.
The report published yesterday shows people tend to report crime most frequently where insurance claims require that the offence be reported to the Garda. In respect of car thefts, for instance, the CSO survey found 95 per cent of car thefts were reported. There was also a high percentage of reporting of burglaries (78.6 per cent).
Just over 40 per cent of respondents said they had suffered thefts from their vehicles but did not report these crimes to the Garda. A similar number did not report the theft of bicycles.
About 30,000 respondents said they had experienced theft without violence but only 48.5 per cent reported the crime.
Around 40 per cent of people who said they suffered crimes involving violence against them did not make reports. Some 17,700 people said they had suffered theft with violence but only 61.5 per cent had reported the crime. Some 17,200 people said they had been assaulted (without suffering theft), but only 62.7 per cent had reported these crimes.
The report says 38.5 per cent of people who experienced theft involving violence did not make a report to the Garda.
In giving reasons, 39.7 per cent said they did not consider the theft with violence to be "serious enough" or suffered no loss.
Some 16.5 per cent said they did not make any report because they believed gardai could either do nothing or because they felt there was lack of proof. Another 7.7 per cent said they believed the Garda would do nothing about their report.
Twelve per cent said they "solved it themselves". Almost 7 per cent said they reported the robbery to another authority. Some 4.7 per cent said they simply did not want to involve the Garda and another 4.6 per cent said they made no report for fear of reprisal.