Raymond V. Liedka, of Oakland University in Michigan, and colleagues have found that the crime-fighting effects of prison disappear once the incarceration rate gets too high. ‘If the buildup goes beyond a tipping point, then additional incarceration is not going to gain our society any reduction in crime, and may lead to increased crime,’ Dr. Liedka said.

I have heard it argued, often tepidly, that harsh sentencing for non-violent crimes like drug possession and distribution trespasses against justice. A recent article in the New York Times gives new teeth to that claim.

Criminologists, epidemiologists, and sociologists have studied the effects of incarceration on families and communities. They have discovered that, after a certain point, raising incarceration rates distressingly reinforces patterns of poverty and criminality rather than dismantling them. The prison system drains communities of human capital, deprives families of breadwinners, reduces the number of potential mates (usually for for women, and so encourages women to tolerate indignities more readily), induces virtually fatherless boys to physical aggression… the list continues, bleakly and relentlessly.

New York City exemplifies, at least in a limited way, a different and yet successful model. A related article from January details how New York has lowered its crime rate by 75%, all the while drastically lowering the number of people in its jails and prisons. It turns out that the money saved in the penal system reaps abundant rewards when applied to the police force.

Would not our laws be more just if they took account of this new scientific data? Our laws reflect justice insofar as they express and protect public goods – and they also reflect their human legislators. In this way, laws can also codify our imperfections and even our sinfulness. With the data at hand that our current system causes more damage to communities than it ameliorates, perhaps more legislators ought to look to New York’s lead.