Prisoners are kept in cages in the exercise yard for the 4B Security Housing Unit at the prison. There are two facilities for SHU inmates at Corcoran, one for gang associates and those who say they want to drop out of gangs, another for verified gang members and high-risk inmates.

Prisoners are kept in cages in the exercise yard for the 4B Security Housing Unit at the prison. There are two facilities for SHU inmates at Corcoran, one for gang associates and those who say they want to drop out of gangs, another for verified gang members and high-risk inmates.

  An inmate does pull-ups in the exercise yard outside. There are 1,258 men in the Security Housing Units at Corcoran State Prison. They spend between three and four hours outside each day in cages, the rest of the time in 8-by-10-foot cells.

An inmate does pull-ups in the exercise yard outside. There are 1,258 men in the Security Housing Units at Corcoran State Prison. They spend between three and four hours outside each day in cages, the rest of the time in 8-by-10-foot cells.

 A holding cage inside a SHU cell block. Prisoners usually end up in the SHU because of suspected ties to prison gangs with names like Nuestra Familia, the Nazi Low Riders, the Aryan Brotherhood and the Black Guerrilla Family.

A holding cage inside a SHU cell block. Prisoners usually end up in the SHU because of suspected ties to prison gangs with names like Nuestra Familia, the Nazi Low Riders, the Aryan Brotherhood and the Black Guerrilla Family.

  Prison guards sprint to the source of an alarm sounding over the exercise yard. It turned out to be a false alarm.  Cororcoran State Prison has a yearly operating budget of $192 million.

Prison guards sprint to the source of an alarm sounding over the exercise yard. It turned out to be a false alarm. Cororcoran State Prison has a yearly operating budget of $192 million.

 Charles Moore of Oakland is an inmate in the Security Housing Unit at Corcoran State Prison. In October 2013, about 70 accused gang members from Corcoran’s SHU had been released to the general population under a new review process.

Charles Moore of Oakland is an inmate in the Security Housing Unit at Corcoran State Prison. In October 2013, about 70 accused gang members from Corcoran’s SHU had been released to the general population under a new review process.

  Officer Weber stands guard outside the exercise cages of a Corcoran Security Housing Unit with a bottle of mace the size of a fire extinguisher. At the time of the hunger strike in 2013, California had  nearly 4,000 inmates in segregation cells and another 6,600 in temporary isolation.

Officer Weber stands guard outside the exercise cages of a Corcoran Security Housing Unit with a bottle of mace the size of a fire extinguisher. At the time of the hunger strike in 2013, California had nearly 4,000 inmates in segregation cells and another 6,600 in temporary isolation.

  Some men exercise alone in the cages outside, doing pull-ups and walking in circles around the cage. There is an open shower and toilet in each cage.  The state of California spends at least 20 percent more to keep inmates in SHUs – more than $12,000 per inmate per year.

Some men exercise alone in the cages outside, doing pull-ups and walking in circles around the cage. There is an open shower and toilet in each cage. The state of California spends at least 20 percent more to keep inmates in SHUs – more than $12,000 per inmate per year.

 In recent years, inmates housed in SHUs have staged mass hunger strikes to protest conditions inside isolation. The most strike lasted 60 days in from July to September in 2013. It began with 30,000 prisoners and 100 remained on strike when it ended. California state judges approved force-feeding of prisoners.

In recent years, inmates housed in SHUs have staged mass hunger strikes to protest conditions inside isolation. The most strike lasted 60 days in from July to September in 2013. It began with 30,000 prisoners and 100 remained on strike when it ended. California state judges approved force-feeding of prisoners.

 Prisoners are assigned to SHUs based on evidence presented in closed hearings that rarely last more than 20 minutes. Getting out of the SHU requires an inmate to either divulge information about prison gangs or prove he is no longer affiliated. For very different reasons, neither is easy.

Prisoners are assigned to SHUs based on evidence presented in closed hearings that rarely last more than 20 minutes. Getting out of the SHU requires an inmate to either divulge information about prison gangs or prove he is no longer affiliated. For very different reasons, neither is easy.