No country on Earth imprisons more people per capita than the United States. But for America, mass incarceration has proved a losing proposition. The Supreme Court recently found California’s overcrowded prisons unconstitutional, and state legislators want to cut the vast amounts of public money spent on prison warehousing.

Why are so many Americans in prison, and which ones can be safely released? Let’s address some common misunderstandings about our incarceration problem.

1. Crime has fallen because incarceration has risen.

U.S. crime rates are the lowest in 40 years, but it’s not clear how much of this drop is a result of locking up more people.

In Canada, for example, violent crime declined in the 1990s almost as much as it did in the United States. Yet, Canada’s prison population dropped during this time, and its per capita incarceration rate is about one-seventh that of the United States. Moreover, while U.S. incarceration rates have steadily risen for four decades, our crime rate has fluctuated — rising through the 1970s, falling and then rising in the 1980s, and falling since 1993.

Harvard University sociologist Bruce Western believes that increased incarceration accounts for only about 10 percent of the drop in crime rates; William Spelman, a professor of public affairs at the University of Texas, puts the figure at about 25 percent. Even if the higher figure is accurate, three-quarters of the crime decline had nothing to do with imprisonment. Other causes include changes in drug markets, policing strategies and community initiatives to reshape behavior.

2. The prison population is rising because more people are being sentenced to prison. In the 1980s and early 1990s, the number of people sent to prison grew mainly because of the war on drugs. The number of drug offenders sentenced to state prisons increased by more than 300 percent from 1985 to 1995.

Since then, however, longer prison terms more than new prison sentences have fueled the prison population expansion. These are a result of mandatory sentencing measures such as “three strikes” laws and limits on parole release. Today, 140,000 prisoners, or one of 11 inmates, are incarcerated for life, many with no chance of parole.

Longer stays in prison offer diminishing returns for public safety. As prisoners age, the likelihood that they will commit crimes drops, but the cost of their imprisonment rises, primarily because of increased medical care. Harsher sentences also offer little deterrence: When people consider committing crimes, they may think about whether they will be caught, but probably not about how harshly they will be punished. In 1999, the Institute of Criminology at Cambridge University reviewed studies of deterrence and sentencing and found no basis “for inferring that increasing the severity of sentences generally is capable of enhancing deterrent effects.”

3. Helping prisoners rejoin society will substantially reduce the prison population. Ninety-five percent of American prisoners will return home someday. While reentry programs can aid reintegration into the community, they do little to reduce our reliance on incarceration. Prison appears to make inmates as likely to commit crime as not; about half of released inmates return to prison within three years. Congress appropriated only $83 million for reentry in fiscal year 2011, or less than $120 per released prisoner. Even with additional state funds, one is not likely to overcome a lifetime of low educational attainment, substance abuse and/or mental health disabilities with this meager commitment.

Investing in prevention and treatment instead of imprisonment is more likely to shrink the prison population. The Washington State Institute for Public Policy, for example, found that home-based supervision of juvenile offenders produced $28 in taxpayer benefits for every dollar invested.

4. There’s a link between race and crime. Yes, African Americans and Latinos disproportionately commit certain crimes. But in a 1996 study of crime rates in Columbus, Ohio, criminologists from Ohio State University concluded that socioeconomic disadvantages “explain the overwhelming portion of the difference in crime.”

Nowhere are racial disparities in criminal justice more evident than in drug law enforcement. In 2003, black men were nearly 12 times more likely to be sent to prison for a drug offense than white men. Yet, national household surveys show that whites and African Americans use and sell drugs at roughly the same rates. African Americans, who are 12 percent of the population and about 14 percent of drug users, make up 34 percent of those arrested for drug offenses and 45 percent of those serving time for such offenses in state prisons. Why?

In large measure, because police find drugs where they look for them. Inner-city, open-air drug markets are easier to bust than those that operate out of suburban basements, and numerous studies show that minorities are stopped by police more often than whites. For example, a Center for Constitutional Rights study found that 87 percent of the 575,000 people stopped by the police in New York City in 2009 were African American or Latino.

5. Racial disparities in incarceration reflect police and judges’ racial prejudice.

Shocking instances of racism still come to light in the justice system. But racist cops and courts are not the primary reason for racial disparities in incarceration.

Consider increased penalties for drug offenses in school zones. Though not racially motivated, these laws disproportionately affect minorities, who more often live in densely populated urban areas with many nearby schools. In New Jersey, for example, 96 percent of people incarcerated under such laws in 2005 were African American or Latino. Judges didn’t necessarily want to sentence these defendants to more prison time than those convicted outside school zones, but under the law, they had to.

Where we spend money also contributes to the problem. The Violent Crime Control and Law Enforcement Act of 1994 appropriated $9.7 billion for prisons and $13.6 billion for law enforcement, but only $6.1 billion for crime prevention. Politicians eager to be seen as tough on crime too often find ways to fund new prison cells, even though they know that minorities will predominantly fill them. This isn’t the fault of racist individuals. It’s the fault of a system that fails to take the promise of equality seriously.

The United States imprisons a larger proportion of its population than Russia or Belarus. Our incarceration rate is eight times that of France. These tragic statistics force us to ask: Would the American public accept these rates if incarceration were distributed more equally across race and class?

mauer@sentencingproject.org

cole@law.georgetown.edu

Marc Mauer is executive director of the Sentencing Project. David Cole is a professor at Georgetown University Law Center.

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