Americans stay in prison longer, and for a wider range of offenses, than their counterparts in other nations. The United States had 2.3 million people in prison or jail in 2007—more than any other country in the world. That’s nearly 751 incarcerated individuals for every 100,000 in the population. The median for all nations is 125 people per 100,000. For some groups, the numbers are especially alarming: about 1 in 36 Hispanic adults and 1 in 15 African American adults have been in prison. In fact, 1 in 9 African American men aged 20-34 have been in prison. Since the mid-1970s, the state prison population in the United States has nearly quadrupled and the rate of incarceration in local jails has more than tripled.

Why are so many Americans in prison and what factors explain the dramatic increase in incarceration rates in such a short period of time? How has our large prison population influenced crime rates and what has it cost American communities? Just as important, what are the roles of harsher sentencing laws, the legacy of racial discrimination, and the lack of an effective social safety net?

Why Are There So Many Americans in Prison?

Incarceration in the United States – Wikipedia

The accelerating rate of incarceration over the past few decades is just as startling as the number of people jailed: in 1980, there were about two hundred and twenty people incarcerated for every hundred thousand Americans; by 2010, the number had more than tripled, to seven hundred and thirty-one. No other country even approaches that. In the past two decades, the money that states spend on prisons has risen at six times the rate of spending on higher education. Ours is, bottom to top, a “carceral state,” in the flat verdict of Conrad Black, the former conservative press lord and newly minted reformer, who right now finds himself imprisoned in Florida, thereby adding a new twist to an old joke: A conservative is a liberal who’s been mugged; a liberal is a conservative who’s been indicted; and a passionate prison reformer is a conservative who’s in one.
. . .
William J. Stuntz, a professor at Harvard Law School who died shortly before his masterwork, “The Collapse of American Criminal Justice,” was published, last fall, is the most forceful advocate for the view that the scandal of our prisons derives from the Enlightenment-era, “procedural” nature of American justice. He runs through the immediate causes of the incarceration epidemic: the growth of post-Rockefeller drug laws, which punished minor drug offenses with major prison time; “zero tolerance” policing, which added to the group; mandatory-sentencing laws, which prevented judges from exercising judgment.

The Caging of America: Why do we lock up so many people?

The Collapse of American Criminal Justice – Google Books

Entire world – Prison Population Rates per 100,000 of the national population

Prison Population – Pew