Almost half of the prisoners released from Irish jails in 2011 and 2012 were convicted of further crimes within three years, according to data released on Tuesday.
Sex offenders were the least likely to be convicted of more crimes within three years and those convicted of robbery crimes were the most likely to reoffend, the Central Statistics Office show.
Younger offenders were also far more likely to be convicted again after release from prison than older released prisoners.
Some 48.9 per cent of the criminals, of all ages and serving sentences for a wide range of offences, released in 2011 had been reconvicted within three years. This compared to 45.8 per cent of those released in 2012 being convicted for at least one other crime within three years.
The data shows a falling recidivism rate in recent years; some 51 per cent of prisoners released in 2008 reoffended within three years compared to 45.8 per cent four years later.
The data shows that those jailed for robbery, extortion and hijacking offences were most likely to be reconvicted three years later; some 72.3 per cent.
Some 69.4 per cent of burglars released in 2012 had been convicted again within three years.
Other rates of recidivism included: Theft and related offences at 61.6 per cent; fraud and deception offences at 21.7 per cent; drug crimes at 44 per cent.
Of those released from prison sentences in 2012 for sexual offences, some 18.9 per cent had been convicted again within three years.
Male prisoners were also much more likely to re-offend than women, a gap which has widened. In 2008 the male recidivism rate was 51.5 per cent; just over five per centage points higher than for women. But by 2012 it had more than double to just under 12 per centage points, with a male recidivism rate of 47.6 per cent against a female rate of 36 per cent.
Young men aged 20 years or younger when released from jail in 2012 were the most likely of any group to be convicted of new crimes; some 74 per cent of that cohort recording a new conviction within three years of release.
Those prisoners aged 51 years or older were least likely to be convicted again; just 23 per cent.
The CSO has not commented on the reasons for the generally declining recidivism rate when all crime types are combined.
However, security sources point out that as the economy crashed from 2008 crime rates declined in the Republic. Declining crime rates would be reflected in a lower recidivism rate.
Around 2009-2010 the number of gardaí in the Republic also began falling as recruitment to the force was halted. Many in the Garda believe fewer criminals were detected committing crimes because of falling Garda numbers.
The figures are calculated from records by the Irish Prison Service with the Garda PULSE system. The CSO categorises them as “under reservation” amid its ongoing concerns over recording of Garda statistics.