The Making of the Map

How much does it cost to keep somebody locked up? This map, created by Eric Cadora and Charles Swartz, illustrates the estimated cost per block for people who entered the state prison system in 2003. To make the map, Cadora and Swartz obtained home addresses and prison sentences—like three to six years—for everyone who was sent to prison in 2003. Then they took each person's minimum sentence (in the above example, that would be three years) and multiplied that number by $30,000 in order to figure out what the total expense will be for his or her incarceration.

The estimates shown on this map are conservative. Many inmates remain in prison longer than their minimum sentence. And the figure of $30,000 may be lower than the actual cost per year to hold an inmate in a New York State prison. (The state Department of Correctional Services puts this number at $26,933, but a recent report from the federal Bureau of Justice Statistics gives it as $36,835.)

In addition, this map features only prison costs—not jail costs. Prisons hold people who have been convicted of a crime; jails, like those on Rikers Island, are for people who have been accused of a crime and are not yet convicted, or for people who have received sentences of one year or less.

The darkest red areas on this map are "million-dollar blocks"—blocks where so many people were sent to prison in 2003 that the total cost of their incarceration will exceed a million dollars. There would have been many more "million-dollar blocks" if jail expenses were factored in. And the price tag per block would climb even higher if other criminal-justice costs—like those for probation and parole—were also added. As it is, in 2003, there were 35 million-dollar blocks in Brooklyn, out of a total of 9,589 blocks.