A recent report suggests how locking more prisoners up for longer may not result in lower crime rates after all.

The topic of criminal justice has come to the forefront of popular culture, thanks to TV shows like Netflix’s “Making a Murderer” and the hit podcast “Serial.” But what may be less commonly discussed— but is an equally important component to the conversation, experts say—is the connection between an individual’s prison time and the effect that sentence may have on crime rates in his or her community.

Public safety

While it may be intuitive to think that keeping prisoners incarcerated for as long as possible is effective for reducing crime rates, a recent report conducted by the Sentencing Project suggests that criminal justice policy is more important for this effect. The report ultimately suggests that releasing inmates from jail can be done without harming public safety.

“While some political leaders warn of a ‘crime wave’ when prison population reductions are considered, such talk ignores the complexity of how public safety is produced,” the Sentencing Project, a Washington D.C.-based nonprofit that advocates for criminal justice, says in its report, says in its report. “Incarceration is a limited factor among many that shape public safety.”

Safer streets

The group drew prisoner population and crime data in all 50 U.S. states from between 2006 and 2012, and deduced that during periods of greater decarceration, violent crime rates in three states—New York, New Jersey and California—fell at a faster rate than they did nationwide. For the former two states, property crime rates also fell at a greater rate.

Policy changes that may account for those dips in crime rates vary by state— ranging from policing changes, to parole review rules, to rules that determine whether an individual is admitted to a county jail or a state prison.

But, the group concludes, “policy decisions, and not levels of crime, have been the main determinant of the scale of incarceration.”

The Sentencing Project also expresses skepticism about the idea that reducing incarceration time leads to greater recidivism, or the repeat of a criminal offense after decarceration. The report lists a handful of theories as to why less prison time doesn’t equate to recidivism— among them, a criminogenic effect, meaning that the longer a person is in prison, the harder it is to maintain their relationship with their friends and family members.

A shift in priorities

The report supports observations drawn from scientific research on the effect that decarceration can have in producing lower crime rates. For example, a National Academy of Sciences panel led by Jeremy Travis, president of the John Jay College of Criminal Justice, found a modest association between those two factors.

Based on its findings, the Sentencing Project called for a shift in priorities among officials to promote taxpayer savings as well as criminal justice and, ultimately, public safety.

“Rather than preventing or addressing crime through job creation, mental health and substance abuse treatment and other interventions, far too often arrest and incarceration have become the preferred options,” the group says.