Washington, May 19 (ANI): Former prisoners are less likely to return to jail if they expect longer sentences for future crimes, according to a study.
The study-conducted by researchers from the University of Naples Parthenope, France-based National Centre for Scientific Research (CNRS), and University of Bergamo-used a recently passed Italian law as a natural experiment.
"This paper contributes to the literature providing evidence that potential criminals do respond to a change in prison sentences," write the study's authors.
They say that Italy's Collective Clemency Bill, which was passed in 2006, presents a unique opportunity to study the deterrent effect of prison sentences.
They point out that when the clemency bill was passed, it immediately released thousands of prisoners who had three years or less left on their sentences. The remainder of each prisoner's sentence was suspended, but not forgiven.
According to the authors, the law stipulated that a former inmate who commits a new crime within five years will have the suspended portion of his sentence reinstated and added to the sentence for the new crime.
Consequently, a repeat offender can expect extra jail time equal to the suspended portion of his sentence-anywhere from one month to three years.
The researchers used government data to look at the recidivism rates of the hese former inmates for the first seven months after their release, and found that those with longer suspended sentences-and therefore longer expected sentences for new crimes-were less likely to be re-arrested than those with shorter suspended sentences.
"These results corroborate the general theory of deterrence," the authors write.
Their calculations suggested, "increasing the expected sentence by 50 percent should reduce recidivism rates by about 35 percent in seven months."
However, even a small increase in the expected sentence was enough to deter recidivism at least a little, the team found.
The data suggest that a one-month increase in expected sentence resulted in a 1.3 percent lower probability of returning to prison.
The deterrent effect was consistent across age groups, and among men and women, though 95 percent of the sample was male.
"This means that a policy a commuting actual sentences in expected sentences significantly reduces recidivism. A mass release of prisoners can be effective in reducing their propensity of re-committing crimes if, when a released individual gets convicted of a new crime, his normal sentence is increased by the time that was pardoned because of the early release," Dr. Vertova says.
The researchers, however, write that one important exception to the deterrent effect was that recidivism rates among those whose original crime was more serious were essentially unaffected by the length of their suspended sentence, which suggests that "more dangerous inmates are not deterred."
They also caution that their results only measure deterrence on those who have already served time in jail.
"Indeed, it is not clear whether these results can be to individuals who have never received prison treatment," they noted.
However, despite the limitations, the study does provide real-world evidence that "individuals vary their criminal activity in response to a change in prison sentences," the authors write.
The study has been reported in the Journal of Political Economy. (ANI)