According to the most recent data, federal prisons hold nearly 96,000 inmates for drug offenses (about 50% of all federal inmates) and state prisons hold 208,000 (about 16% of all state inmates). Another 184,000 people are in local jails for drug law violations, for about 490,000 Americans total. There were 1.5 million arrests for drug crimes in 2014.

In 2004, about half of drug offenders in federal prisons and one-fifth of those in state prisons were convicted for marijuana-related crimes, 45,000 people total.

Nearly half a million people in prison for drugs is equivalent to the size of some major U.S. cities. It is higher than the populations of Sacramento, Kansas City, Atlanta, Minneapolis, St. Louis, Miami, or Pittsburgh.

The Sentencing Project writes that

the number of Americans incarcerated for drug offenses has skyrocketed from 41,000 in 1980 to nearly a half million in 2014. Furthermore, harsh sentencing laws such as mandatory minimums keep many people convicted of drug offenses in prison for longer periods of time: in 1986, people released after serving time for a federal drug offense had spent an average of 22 months in prison. By 2004, people convicted on federal drug offenses were expected to serve almost three times that length: 62 months in prison.

Further, although whites and blacks use drugs at equal rates, blacks are much more likely to be arrested and imprisoned for drug use, and serve longer sentences than whites who commit the same crimes.

What is the cost of holding so many nonviolent offenders?

The Vera Institute of Justice found the average cost to keep one person behind bars is $31,000 a year (in some states like New York, it’s closer to $60,000), a cost funded by taxpayers. This means the cost of housing drug offenders alone (using the average cost) is about $9.4 billion each year for state and federal prisoners, $15.1 billion a year when you add in local jails.

According to the Drug Policy Alliance, the U.S. spends $51 billion a year on the War on Drugs.

2.2 million people are in prison, for all crimes — the highest incarceration rate in the world.

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