Econometric support for cutting prison populations

When Texas Monthly editor Jake Silverstein asked me to contribute a "Big Idea" for the magazine's May issue on the subject, I'd offered them this provocation, crafted from material in past Grits posts:

Texas should dramatically slash its prison population and eliminate a majority of felony crimes. We have criminalized too many different activities: Texas has 2,324 separate felonies on the books, including 11 involving oysters. From 1978 to 2008, Texas's population increased 80 percent, while the prison population increased 595 percent. If prison growth had matched population growth, around 40,000 would be in Texas prisons today - instead the number is about 155,000. Texas must stop trying to manage every social problem through the justice system and re-empower its civil courts and regulatory functions to handle more conflicts among citizens.

My suggestion for slashing the prison population was met in some quarters with derision. "WOW!! I could not disagree more with your opinions on this issue," opined one reader. A GOP legislative staffer at the capitol told me she was shocked to see me put my name on such "radical" views.

So I'm plesaed to be reading a new paper by UT-Austin LBJ School Professor Bill Spelman ("Crime, cash and limited options: Explaining the prison boom," Criminology & Public Policy, Vol. 8, No. 1., pp. 29-77, not online, see the abstract), confirming in laborious detail the mathematics behind the following calculation:

Estimates vary widely, but the marginal prison bed seems to prevent somewhtere between two and seven crimes, which saves potential victims between $4,000 and $19,000 per year.

"But note the details: If each prison bed reduces costs by no more than $19,000, but costs us $20,000 to $40,000, then do we need this many beds? Clearly not, and it's not (too) difficult to use current estimates of the crime-control effectiveness of prison, the costs of crime to victims and nonvictims, and the costs of prison to show that we overshot the mark sometime in the early 1990s. Enormous cutbacks - reductions of 50% or more in the prison popoulation - are not difficult to justify and would probably save the US public billions of dollars earch year. Certainly there is little economic justification for continuing to build.

The wide variation among estimates for crime costs prevented by prison make the cost-benefit analysis even dicier than that quote implies. $19,000 is the high end of estimated crime costs prevented by incarceration. If the true cost turns out to be closer to $4K, on the low end of the spectrum, then from an economic perpective overincarceration would seem abusrdly overemphasized.

Spelman's analytical work on this subject ranks among the most respected on all sides of the debate. And though I've quibbled with some of the assumptions in his work, including in this paper, on the whole there's really nobody out there whose approach is both as comprehensive and data driven as what he's producing. I'll be writing more about Spelman's findings soon, perhaps after talking to Bill about his paper, just to make sure I understand his math.

Prof. Spelman, incidentally, was previously on the Austin City Council and after a hiatus, was just re-elected to an open seat unopposed. Congrats, Bill!