Is America’s incarceration rate “about to fall off a cliff”?

The question in the title of this post is prompted by this new article by Keith Humphreys in The Atlantic headlined “America’s Incarceration Rate Is About to Fall Off a Cliff.” I recommend the article in full because there are nuances to the argument not captured in excerpts.  But here are excerpts:

For more than 40 years, the United States — a nation that putatively cherishes freedom — has had one of the largest prison systems in the world.  Mass incarceration has been so persistent and pervasive that reform groups dedicated to reducing the prison population by half have often been derided as made up of fantasists.  But the next decade could see this goal met and exceeded: After peaking at just more than 1.6 million Americans in 2009, the prison population was just more than 1.2 million at the end of 2023 (the most recent year for which data are available), and is on track to fall to about 600,000 — a decline of roughly 60 percent….

Until 2009, the lengthier sentences handed down during the preceding crime wave and the tendency of released prisoners to be re-incarcerated kept imprisonment rising even as crime declined. But the falling crime that the U.S. experienced in the 1990s and 2000s is now finally translating into a shrinking prison population….

One statistic vividly illustrates the change: In 2007, the imprisonment rate for 18- and 19-year-old men was more than five times that of men over the age of 64. But today, men in those normally crime-prone late-adolescent years are imprisoned at half the rate that senior citizens are today.

As the snake digests the pig year after year, the American prison system is simply not going to have enough inmates to justify its continued size or staggering costs. Some states that are contemplating expanding their prison capacity will be wasting their money — their facilities will be overbuilt and underused.  By 2035, the overall imprisonment rate could be as low as 200 per 100,000 people.  States should instead be tearing down their most deteriorated and inhumane correctional facilities, confident that they will not need the space….

In any given future year, small rises in imprisonment are possible, but the macro trend is ineluctable: Society is going to experience the benefits of past decades of lower crime throughout its prison system. The imprisonment rate will be lower in five years and lower still in 10.  Prisons will still exist then and still be needed, but the rate at which Americans are confined in them could be lower than anything in the preceding half century.  This is the fruit of a lower-crime society — good in and of itself, surely, particularly for the low-income and majority-minority communities where most crime occurs. It will also, of course, be a blessing for those who avoid prison, and for the taxpayers who no longer have to pay for it.  The decline in the prison population will be something everyone in our polarized society will have reason to celebrate.

I largely agree with many aspects of Humphreys’ analysis here, but I am not quite as bullish as he is about the continuing decline of national prison populations.  Because so many tangible and intangible, known and unknown, factors impact both crime and incarceration rates, I do not view any trenda is inevitable (or even likley) in these spaces.  But it sure would be great if, year after year after year for the foreseeanle future, we all get to celebrate less crime and less incarceration.