Kevork Djansezian / Getty Images Inmates at a state prison in Chino, Calif., exercise in the yard

Early this week a bit of cheery news was reported by the Manhattan Institute, a conservative think tank: black segregation has hit its lowest point in more than a century — declining in all 85 of the nation’s largest metropolitan areas. In a stunning turn of events, we are told that “ghetto neighborhoods have witnessed profound population decline, as former residents decamp for the suburbs.”

The report dutifully acknowledges that we still have a long way to go. The study’s authors, Harvard economics professor Edward Glaeser and Duke University professor Jacob Vigdor, explain that “[t]he typical urban African American lives in a housing market where more than half of the black population would need to move in order to achieve complete integration.” Nevertheless, the report is largely celebratory in tone, and it has been received in that fashion by much of the news media.

Before we break out the champagne, however, it may be wise to pause and reflect for a moment on who was excluded from the analysis.

Our nation’s prison population has more than quintupled (soaring from 300,000 in the mid-1970s to more than 2 million today), due to a “get tough” movement and a war on drugs that has been waged almost exclusively in poor communities of color. Studies have consistently shown that people of color are no more likely to use or sell illegal drugs than whites, but a fierce drug war has been waged nonetheless, and harsh mandatory minimum sentences passed, leading to a prison-building boom unprecedented in world history. Despite this sea change, prisoners continue to be treated as nonentities in much sociological and economic analysis.

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In the Manhattan Institute study, prisoners are not even mentioned, despite the fact that millions of poor people — overwhelmingly people of color — are removed from their communities and held in prisons, often hundreds of miles from home. Most new prison construction has occurred in predominately white, rural communities, and thus a new and bizarre form of segregation has emerged in recent years. Ghetto youth are transferred from their decrepit, underfunded, racially segregated schools to brand new, high-tech prisons located in white rural counties.

In a sense, mass incarceration has emerged as a far more extreme form of physical and residential segregation than Jim Crow segregation. Rather than merely shunting people of color to the other side of town, people are locked in literal cages — en masse. Bars and walls keep hundreds of thousands away from mainstream society — a form of apartheid unlike the world has even seen. If all of them suddenly returned, they would not be sprinkled evenly throughout the nation’s population. Instead they would return to a relatively small number of communities defined by race and class, greatly intensifying the levels of segregation we see today. The likelihood of many escaping their ghettoized communities and landing in racially integrated, well-manicured suburbs is slim, given that people labeled criminals and felons can be legally discriminated against for the rest of their lives in employment, housing, access to education and public benefits — even denied food stamps. Although most people sent to prison are convicted of relatively minor, nonviolent crimes and drug offenses, they are treated as perpetual threats and locked in a permanent undercaste.

Those who imagine that the failure to account for prisoners can’t possibly affect the analysis would be wise to consider the distortion of unemployment figures in recent years. Because standard unemployment reports continue to exclude prisoners, we have been treated to a highly misleading picture of black unemployment. According to Harvard professor Bruce Western, standard unemployment figures underestimate the true jobless rate by as much as 24 percentage points for less educated black men. In fact, during the 1990s — the economic-boom years — noncollege black men were the only group that experienced a sharp increase in unemployment, a development directly traceable to the sudden explosion of the prison population. At the same time that unemployment rates were sinking to record low levels for the general population, the true jobless rate among noncollege black men soared to a staggering 42% (65% for black male drop outs.)

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Prisoners do matter when analyzing the severity of racial inequality in the U.S. Yet because they are out of sight and out of mind, it is easy to imagine that we are making far more racial progress than we actually are. For now, let’s keep the cork in the bottle and pray that we will eventually awaken from our color-blind slumber to the persistent realities of race in America.