The effect of prison on adult re-offending

Release Date: 21 September 2010

Prison does nothing to deter adult offenders convicted of burglary or assault. In fact it may even increase the risk of re-offending, a new study by the NSW Bureau of Crime Statistics has found.

To conduct the study, the Bureau compared 96 matched pairs of convicted burglars and 406 matched pairs of offenders convicted of non-aggravated assault.

One member of each pair received a prison sentence, while the other received some form of non-custodial sanction.

All offenders were exactly matched on offence type, number of concurrent offences, prior prison experience, number of prior appearances in court and bail status at final appearance.

Statistical methods were used to control for age, age of first conviction, gender, race, plea, number of counts of the principal offence, legal representation and prior breach of a court order. In the case of non-aggravated assault an additional control was included: prior conviction for a violent offence.

The study found that offenders who received a prison sentence were slightly more likely to re-offend than those who received a noncustodial penalty.

The difference was just significant for non-aggravated assault but not significant for burglary.

Commenting on the findings, the Director of the Bureau, Dr Don Weatherburn, said that they were consistent with a growing body of evidence suggesting that prison either does nothing to deter offenders or increases the risk of re-offending.

"This does not mean that prison should be abandoned and all prisoners set free. Prison can be justified on other grounds, such as punishment and incapacitation."

The present study simply shows that sending people convicted of assault or burglary to prison is no more effective in changing their behaviour than putting them on some form of community-based order. In fact it might be slightly worse."

Further enquires: Dr Don Weatherburn 9231-9190 or 0419-494-408
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