RALEIGH — While not being much in evidence in recent years, the issue of overcrowded prisons has played a significant role in North Carolina politics over the past generation. Now, as two different news stories during the Christmas holidays revealed, the problem is making headlines and presenting state officials with difficult challenges once again.

I’m not going to repeat what Freedom Newspapers’ Barry Smith and The News & Observer‘s Dan Kane have already written about with significant perceptiveness and detail. Rather, let me sketch out the parameters of the debate as it existed more than a decade ago — parameters that haven’t shifted much since then.

During the 1970s and 1980s, lawsuits and a surge in violent crime led North Carolina governors and legislators to ponder the best mix of sentencing reforms, prison expansion, and alternatives to incarceration to address a widening gap between spacing needs and capacity. By the early 1990s, there was quite a spectrum of views on the matter, a divergence that was ultimately reflected in public votes and legislation that implemented versions of each faction’s favored policy.

Conservatives advocated a traditionally tough approach of longer sentences, sparse conditions, and significant taxpayer expenditures if necessary to build enough prison capacity to combat the crime wave. Many liberals argued that expanding prisons shouldn’t be the priority, that too many nonviolent offenders were serving time instead of being diverted to alternative punishments such as intensive probation and house arrest. Others argued that the state’s drug laws were to blame, since the spike in incarcerations appeared to coincide with changes in drug trafficking and usage. Still other, “root-causes” analysts suggested that by spending more money on social programs and education — particularly aimed at preschool-aged children — the state could head off future crimes and thus save money in the long-run.

While much of the political debate centered around basic principles that were simply not shared, there was some real disagreement about the facts of the prison issues. For example, prison-expansion proponents argued that investing tax dollars today would generate future returns tomorrow through two related processes: incapacitation and deterrence. On incapacitation, the argument was that a relatively small group of career criminals committed a disproportionately large share of the total crimes in the society, especially the more costly and violent ones. Thus, if such hardened felons could be identified and taken off the streets, the crime rate would improve.

Secondly, the deterrence argument suggested that most criminals, despite appearances to the contrary, were essentially rational actors. Their decisions were based on probable costs and benefits. If the potential cost to them for committing crimes went up — if the chances of being apprehended, tried, convicted, and sentenced to lengthy sentences were increased through public expenditure — then fewer would make the decision to commit crimes.

Liberals were having none of this. On the incapacitation issue, they denied that it was possible effectively to identify the core of career thugs responsible for disproportionately criminality. Indeed, they rejected the entire thesis, arguing that current social conditions had generated enough potential criminals that any habitual felons arrested and carted off to prison would be replaced by others (who knew there was a line?). And on deterrence, they typically argued that most criminals were not rational actors, that their decisions were influenced primarily by their perceptions of need and the emotions they felt in the heat of the moment. Indeed, the liberal version of the “career criminal” argument was that by incarcerating so many relatively young, relatively penny-anty criminals in prison, the state was actually manufacturing its own future crop of career criminals from kids who might otherwise be steered to a more peaceful and productive live through alternative programs.

Again, a main theme of the liberal critique of “tough-on-crime” policies such as abolishing parole, policing more aggressively, and implementing “three-strikes” laws was that criminality was a symptom of larger societal maladies — a lack of drug treatment programs, for example, or the economic conditions to which youngsters were subjected — so it was a mistake simply to treat the manifestations and not the underlying illness.

Given that most states, while mixing several of these options, leaned most heavily towards incarceration during the late 1980s and 1990s would seem to offer all sides in the debate an opportunity to test their theories against reality. But an empirical test is only as useful as its interpretation, and diversity continues on that score. The crime rate did drop, after all, so conservatives (properly, in my view) typically claim vindication. On the other hand, skeptics argue that other factors were at work, including an improved economy, better education, and welfare reform (not that they necessarily embraced the policies that likely yielded those outcomes, a topic for another day).

And a few addled liberals, famously concentrated on the national desk of The New York Times, complained about the public-policy scandal they thought wasn’t receiving enough attention: that even during a time of falling crime, hapless and corrupt state officials were continuing to fill and expand their prisons!

Karl Popper, call your office.

Hood is president of the John Locke Foundation and publisher of Carolina Journal.