TWO WEEKS BEFORE he stepped down from office, Barack Obama published an essay on criminal justice reform in the Harvard Law Review, the journal of his old law school. It is a cause for which he campaigned throughout his presidency, but with fewer victories than he had hoped for.

“We should all be able to agree that our resources are better put toward underfunded schools than overfilled jails,” the former president writes, “and that many of those in our criminal justice system would be better and more humanely served by drug treatment programs and the receipt of mental health care.”

But Obama has it wrong, according to Locked In, a new critique of the causes and myths of mass incarceration. In the book, Pfaff, a professor at Fordham University School of Law, argues that reformers’ emphasis on drug crimes, while laudable in principle, has only distracted from the real drivers of the United States’s prison boom.

“[R]eformers still don’t understand the root causes of mass incarceration,” he writes, “so many reforms will be ineffective, if not outright failures.”

While drug offenders make up almost half of the federal prison system and were responsible for a large increase in the federal prison boom that began in the 1970s, most (about 87 percent) of the prisoners in the United States are held within the state system. Here only about 16 percent of the population are locked up for drug charges, and about six percent for nonviolent drug offenses, Pfaff points out. If you release every single person charged with these crimes, you still do not alter the fundamental fact of mass incarceration.

The United States would still have one of the highest incarceration rates in the world, the book notes. It was not always like this. In 1972, there were 200,000 inmates in US prisons; by 2014, there were 1.56 million.

In recent years, bipartisan criticism of this prison boom has begun to gather momentum. Many on the right see mass incarceration as an ineffective use of taxpayer money and an inefficient way to reduce crime. On the left, people consider it to have unacceptable social collateral costs, removing people from their families and communities rather than targeting root causes of crime.

Obama, like many advocates for change, focused his efforts on people incarcerated for drug offenses, who make easy targets for prison reform. In July 2015, he visited El Reno prison in Oklahoma, where he met with a group of nonviolent drug offenders and reiterated his views on the injustice of sending people to prison for these crimes. “A primary driver of this mass incarceration phenomenon is our drug laws,” he said. Academics have also bolstered this assertion. “The uncomfortable reality is that convictions for drug offenses — not violent crime — are the single most important cause of the prison boom in the United States,” writes Michelle Alexander, a law professor at Ohio State University, in The New Jim Crow, which has become a canonical criticism of the US prison system.

Pfaff seeks a correction to what he considers a myth behind Alexander’s and Obama’s charges. “The movement against mass incarceration had no option but to start where it did, focusing on drugs and other nonviolent crimes,” Pfaff writes,

That movement is nearly a decade old now, however, and it is important to pause and acknowledge that the gains have not been great […] Total prison populations outside of California are down by less than 2 percent since 2010 (and by barely 4 percent when we include California).

If not drugs, then, where should reformers focus their efforts? The answers are both politically toxic and likely an impossible sell to an electorate who punish at the polls for perceived increases in crime. The real issue, Pfaff says, is that most of the people locked up — more than half in the state system — are there for violent crimes. This group also explains two-thirds of the growth in prison populations since 1990. “Until we accept that meaningful prison reform means changing how we punish violent crimes, true reform will not be possible,” he writes.

But this increased propensity toward the imprisonment of violent offenders at the state level was not the result of an increase in crime — or even the result of intentional policy changes. Rather, prison growth in recent decades continued even as crime has fallen. It was driven by local decisions among individual prosecutors.

This is Pfaff’s most counterintuitive finding, with profound implications for how to tackle reform. In the early 1990s, violent crime began to fall dramatically; since 1991, it has fallen by 51 percent, according to the Brennan Center for Justice. But prison expansion continued apace. And most of this was because of prosecutors pushing for felony charges with increasing frequency, according to Pfaff. Holding all other factors constant, he shows that the chance of an arrestee being charged with a felony doubled after 1994, which was the driver of an almost 40 percent increase in the US prison population between 1994 and 1998. “While arrests fell, the number of felony cases rose, and steeply,” he explains. “Fewer and fewer people were entering the criminal justice system, but more and more were facing the risk of felony conviction — and thus prison.” Many of these cases are decided in backroom plea bargains, where clients are inadequately represented by time poor and underfunded public lawyers. Short of increased funding for indigent defense, only a change in attitude among prosecutors and the public who elect them will reverse this trend of filing felony charges.

A tilt toward less-punitive measures for violent crimes seems fanciful in the current political climate. Suggestions such as releasing those charged with violent crimes early or making sentencing guidelines for such crimes more lenient would doubtless be dismissed outright by the Trump Administration. Besides promising to lock up his opponent, Donald Trump campaigned on a platform to give greater power to law enforcement agencies and clamp down on violent crime. “We must maintain law and order at the highest levels, or we will cease to have a country, 100 percent,” he said last July.

The book, however, offers another, more sanguine, reading of this election’s implications for prison reform. Despite Trump’s tough on crime rhetoric, Pfaff sees a series of micro-victories for prison reform across the country. Most reform decisions are controlled not by the federal government, but by states, counties, and districts. The same forces that prevented Obama from achieving widespread decarceration will also prevent Trump from doubling down on incarceration unless local politics consents, so goes the argument. And many of the same people who voted for Trump simultaneously supported prison reform at the local level. Oklahoma, which Pfaff cites as an example, gave 65.3 percent of its vote to Trump. On the same day, the state passed State Questions 780 and 781, measures reclassifying certain nonviolent drug offenses and petty thefts as misdemeanors and redirecting savings to mental health and drug treatment instead of prison. Yet, to bring Pfaff’s argument full circle, measures such as this might curb unfair drug sentencing, but will not lead to significant changes in incarceration patterns.

In the end, success by Pfaff’s metrics depends on what reformers, and the public, actually want. Is the aim to bring down the prison population as an end in and of itself or only to stop sending people to prison for misdemeanors and nonviolent crimes? Pfaff’s argument assumes that the public’s qualm with mass incarceration should be with the absolute number of people locked up.

But it is also possible that many reformers would be happy with a small reduction in the prison population, if they felt that the people who remained in prison “deserved” to be there. In other words, the book demands much more than tinkering at the edges with the current model of incarceration. It advocates for a cultural shift among prosecutors and the public, to view prisoners not only as criminals, but also as people who have impulsively and regrettably committed crimes. As people who should be helped rather than merely warehoused and incapacitated. It reads more as a clarion call toward what might one day be than a set of policy formulations that could be easily enacted.

“It may be that some reforms are justifiable even if they do lead to more crime,” Pfaff writes,

It’s true that crime is costly — but so, too, is punishment, especially prison. The real costs are much higher than the $80 billion we spend each year on prisons and jails: they include a host of financial, physical, emotional, and social costs to inmates, their families and communities. Maybe reducing these costs justifies some rises in crime.

This is the book’s most difficult sell. Pfaff admits that he is doubtful leaders will embrace the argument in the short run. It is less politically risky for people to be kept in prison for too long than released too early — or not sent to prison in the first place. But whether the zeitgeist on this issue shifts or not, to those asking why the United States imprisons so many of its people, the answers and hints of possible reform are here. Changing this reality will need much more than emptying prisons of drug offenders.

¤

Josh Jacobs is a writer based in New Haven, Connecticut. He has been published in, among other places, the Financial Times, Haaretz, Reuters, and the Huffington Post.