Photo: itjournalistI published an academic paper back in 1996 that tried to measure the impact that changes in the prison population have on the crime rate. It turns out that this is a hard question.
You can’t just look across states and compare incarceration rates and crime rates, because the places with the worst crime problem will also tend to have the most prisoners.
Holding constant the punishments, the more crime that occurs, the greater the prison population. So correlations just are not very useful for determining whether prisons are effective or not.
“While those crime numbers sound bad, according to my estimates, letting out the prisoners is more or less a wash from a societal cost-benefit perspective.”
What you need is something more like a randomized experiment in which, for extraneous reasons, a whole bunch of prisoners get let out (or a whole bunch of extra criminals get locked up). For obvious reasons, the National Science Foundation would never give me a research grant to do that myself.
Indirectly, however, the A.C.L.U. (or in the California case, another prisoners’ rights group) does the next best thing. It brings lawsuits against state prison systems arguing that the prisons are so overcrowded that they represent “cruel and unusual” punishment. The A.C.L.U. virtually always wins these suits. The state appeals, and roughly a decade after the suit is filed, the court’s initial decision is upheld and the A.C.L.U. is victorious.
As I report in my paper, these lawsuits have a large impact on the prison populations in the affected states. After the suits are filed, but before any court decisions are handed down, prison populations grow more slowly in the litigation states.
The preliminary court decision doesn’t have much of an effect. But when the final verdict is handed down, prison populations shrink by about 15 percent relative to the rest of the country over the next three years.
Yesterday, a prisoners’ rights group won a preliminary decision against the state of California’s prison system. Consistent with my earlier results, the lawsuit already seems to have had some impact on California’s prison population. For instance, in 2007 California’s prison population shrank by about 1 percent, whereas the overall U.S. prison population grew by nearly 2 percent. It will take a few years before a final court decision is handed down, but the likely outcome is that five or six years from now there will be 25,000 fewer inmates than there otherwise would have been.
What does this mean for crime? If my estimates are correct, ultimately violent crime will be roughly 6 percent higher in California than it would have been absent the lawsuit. That is roughly 150 extra homicides a year, 500 additional rapes, and 4,500 more robberies.
While those crime numbers sound bad, according to my estimates, letting out the prisoners is more or less a wash from a societal cost-benefit perspective. The money we save from freeing the prisoners is on the same order of magnitude as the pain and suffering associated with the extra crime.
I do have one very specific policy recommendation to the state of California. If they do a mass release of prisoners, it should be done with strings attached. Namely, if the released prisoner gets convicted of a crime again in the future, his sentence the next time around should be whatever it normally would be plus all of the time that he should have served on his current sentence that gets cut short because of the early release.
This rule would strengthen the incentives for the ex-cons to stay straight. Italy enforced such a policy after a mass release, and it appears to have been quite effective.
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1) “I’ve found this statement quite surprising and can’t help but feel very curious about how “pain and suffering” can be measured against economic benefit. Would you mind expanding on it a bit more”
Its relatively easy, Courts do it all the time in wrongful death suits
2) If it is a wash from a societal perspective, but clearly a big loss for the individuals affected by the crime, society should just build more prisons. The societal cost is zero, and we have fewer individual victims
How on earth is the societal cost zero? You realize this would (typically) involve the State spending millions of tax payer dollars to build, maintain, fund, and staff these prisons, right?
@ #5, oddTodd,
The societal cost of building new prisons is hardly zero. Either taxes will have to go up, or resources will have to be shifted from other programs. The people of California will pay a high price for more prisons.
You mention 500 additional rapes. Seeing as prisoner on prisoner rape goes largely unreported, I wonder how many rapes are avoided by decreasing the prison population.
“The money we save from freeing the prisoners is on the same order of magnitude as the pain and suffering associated with the extra crime.”
What in the world is wrong with your thinking? Are you really this insensitive? In the field of psychology, this kind of thinking (equating financial cost with rape and murder to balance the two) is considered a severe mental illness.
In fact,it is *precisely* this kind of thinking which creates crimes like murder and rape in the first place. “I want that car more than he deserves to live” and the like.
J.Ja
I have seen these economic analysis reports from my work with Corrections people across the country. It may seen insensitive, but for decision-makers they want to see what the decisions impact will have in hard numbers. On the flip side, when an inmate is rehabilitated the benefit to the state is also able to be documented. Instead of wondering how many people we are warehousing in a prison, we should be wondering how many of them we are fixing! Long term it saves us more money to fix them then just house them for a few years.
“I’m pretty sure those extra 150 homicide victims would disagree with you.”
I’m pretty sure they wouldn’t. Their next of kin might, but the dead aren’t talking.
Regarding the “selection effect”, in which prisons choose to only release the least dangerous criminals: Unpunished criminals tend to get worse over time: today’s back-alley mugger may become tomorrow’s hit man. Levitt’s data based on observations of real prison releases: one can presume that if the prisons he’s studying did *not* select their releasees carefully, his prediction would be even more dire.
Those 5,150 victims and their family members would probably rather pay higher taxes than be assaulted or robbed. Unless they’re Ron Paul supporters, of course.
“This rule would strengthen the incentives for the ex-cons to stay straight.”
This is how prosecution already works. You build a history on a criminal, escalating punishments and reducing your willingness to cut deals all the time. The criminals know that when a Prosecutor lets you walk with time served, it’s so next time they can remind the judge of how they gave you a second chance and request the statutory maximum.
Some of the commenters think there might not be an increase in violent crime if California only releases non-violent offenders. Dr. Levitt’s estimate is based on his paper studying 12 other states that had court-imposed prison population limits. Presumably those other states released non-violent offenders first, so unless California has a much higher ratio of non-violent to violent offenders in its prison population, we probably can’t expect a better result.
Also, the observed increase in violent crime following court-mandated prison population caps is a correlation, but not necessarily a direct causation; i.e., that the released prisoners are themselves committing the additional crimes. There may be secondary causes. For example, less fear of incarceration for drug possession may encourage drug use, meaning there’s more money in drug dealing, and more incentive for the violent crimes associated with high level drug dealing.