Solitary confinement in U.S. jails and prisons has recently come under scrutiny, facing challenges in statehouses, the courts and even by President Barack Obama, who recently banned solitary for some juveniles in federal custody. Still, placing certain inmates for long periods alone inside 6-by-10-foot cells for 23 hours each day is the most common correctional tool nationwide used to quell disorder, punish unwanted behavior and handle the most hard-to-control prisoners.
Here's a look at solitary practices across the country:
WHAT IS SOLITARY CONFINEMENT?
Solitary is referred to by many names in different lockups but generally refers to the placement of a prisoner inside a cell for between 22 and 24 hours per day as punishment for breaking internal rules, because the inmate is considered too dangerous or as a form of protective custody.
An estimated 80,000 to 100,000 people in state and federal prisons are held in solitary on any given day, though advocates argue those 2011 federal figures are likely low. Also unknown is how many of the roughly 700,000 daily jail inmates nationwide are serving their time in solitary.
WHERE IS IT BEING REFORMED?
In January, Obama announced that he would ban the use of solitary for juveniles punished for low-level offenses in federal prisons.
In Colorado, legislators in 2014 largely barred corrections officials from placing mentally ill prisoners in long-term solitary confinement.
In California, Maine, Washington and Michigan corrections officials have enacted reforms to reduce the number of inmates serving their time in solitary.
WHAT'S HAPPENING IN NEW YORK?
New York City jail officials have recently reformed how solitary in the jails, eliminating its use for young inmates and those suffering from serious mental illnesses. From March 2014 to the end of January 2016, officials have shrunk the overall number of inmates housed in 23-hour confinement from about 600 to 219.
In December, state prison officials announced broad reforms to their use of solitary for the roughly 4,000 inmates there, saying they would move about 1,100 of them, now put in "the box" for minor or nonviolent offenses, into secure, therapeutic housing units instead.