by Mark Kleiman

Being asked to guest-blog for Ta-Nehisi Coates is a good news/bad news joke. The good news is that it's insanely flattering, like being asked to pinch-hit for Babe Ruth. The bad news is that's insanely flattering precisely because TNC is, in my professional view, one of the great contemporary prose stylists, so it's hard to live up to the assignment.

On the theory that, by sampling from the top percentile of my writing, I can at least avoid dragging down the average too obviously, I've decided to reprise some of my greatest hits as a blogger, rewriting as necessary to adjust for changed circumstances. I'm going to downplay the political-junkie stuff that really gets my blogging juices flowing in favor of the policy-wonkery that I actually do for a living, where I might have some comparative advantage.

I've been worrying about crime and punishment for 30 years now. With both a homicide rate and an incarceration rate that make us an outlier (by about a factor of five) in the civilized world, and with a crime-and-punishment problem both halves of which hit the poorest slice of the African-American community especially hard—homicide is the leading cause of death for black males aged 15 to 30 in most inner-city areas, and a black male teenager who doesn't graduate from high school has a better than even chance of doing prison time before he turns 30 - there's obviously a lot to worry about.

In my academic/public service career, I've had what seem to me like a bunch of good ideas and a few important insights. But I've never had what I thought was a major conceptual breakthrough—until now.

Now, I think I've figured out how to have half as much crime and half as many people behind bars, and to do it over years rather than decades, using techniques we already understand and spending less money on police, courts, and corrections than we spend now. The trick is not to substitute social services for law enforcement, but to get punishment right.

At first blush, there would appear to be a trade off between crime and punishment: if punishment deters offending, then less punishment means more offending. But it's possible to have both less offending and less punishment by substituting convincing threats for the actual infliction of penalties.

There are two central principles of smart punishment:

1.)  For actual human beings as opposed to economically rational expected-utility maximizers, certainty and swiftness of punishment matter a lot more than severity, in part because of behavioral economics and in part because a system that is certain and swift can also be fair, which randomized draconianism isn't, and people are more willing to adjust their behavior if they think the system that's pressing on them is reasonably fair. Moreover, severity is the enemy of certainty and swiftness, because severe punishments chew up scarce capacity and require a lot of time-consuming due process. That's textbook criminology going back to Beccaria, but putting it into practice is tricky.

2.) The more effective a deterrent threat is, the less often is has to be acted on. Because the risk of punishment faced by an offender depends not only on the capacity of the authorities to punish but also on the rate of offending, there is a natural positive feedback in offending rates.  More offending means less risk for each offender; that's the logical structure of a riot.  By the same token, as violation rates fall the risk of being punished for those who do offend rises.   That creates the possibility of "tipping" effects, situations which have both high-violation and low-violation equilibria.  In such a "tipping" situation, even a temporary increase in enforcement can lead to a lasting decrease in violation rates, and - this is the key point—that decrease can be sustained even after the additional enforcement resources are withdrawn.

Principle #2 leads to a strategic proposal:  when there's not enough capacity to deter every possible violator of every rule—as there generally isn't—then it makes sense to concentrate threats on some subset of offenses or offenders or areas, "tip" that subset to the low-offending equilibrium, and then move on. Because enforcement is costly and enforcement capacity is scarce, enforcers and potential violators actually share a common interest in having actual punishment not happen; therefore, authorities ought in general to "telegraph their punches," issuing specific warnings to specific people in order to reduce the cost of the transition from high to low offending. And Principle #1 means that, if you can deliver on the threat of punishment quickly and reliably, you don't need to threaten years in prison to change behavior—days in jail can be perfectly adequate.

At some level, the principles involved are just common sense:  everyone who has successfully raised a child, trained a puppy, coached a sports team, or managed an office uses them. But they're sufficiently far from current practice and discourse in the realm of crime control as to seem revolutionary.

A variety of actual enforcement successes, from the crackdown on squeegee operators and subway vandals in New York and the Cease-Fire gang-homicide intervention in Boston to low-arrest drug market disruptions in High Point and East Hempstead to the HOPE program in Honolulu, illustrate the potential of the focused-deterrence approach to get us out of our current high-crime, high-punishment social trap.

Now of course I could be wrong about this. But it's not just speculation. There's solid analysis, and some real-world evidence, suggesting that this stuff works. And if that's right, the current glacial pace at which new policies are being adopted means that we are inflicting huge amounts of avoidable suffering on crime victims (and potential victims) and offenders (and their families and friends) alike.

Precisely because this new way of thinking about crime control doesn't fit into the canned discourse of either law'n'order conservatives or "root causes" liberals, it has had a great deal of difficulty finding political traction, while the demands it places on the agencies of criminal justice—and especially on the community-corrections system—make it a tough sell bureaucratically. But the costs—partly fiscal, but primarily human—of staying stuck in the discourse of 1985 are intolerably high. A tiny bit of citizen pressure could make a difference.

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