As of late April, 116 Wisconsin prisoners were held in administrative confinement, DOC spokesman Tristan Cook said. Such confinement is used for inmates who pose a threat to staff, self or other inmates or the “security or orderly running of the institution.”

Cook said the agency is aware of the planned hunger strike and “will continue to evaluate and monitor the situation to ensure the health and safety of inmates.”

In June 2015, the state Department of Corrections reduced the maximum stint in solitary confinement for violating prison rules from 360 days to 90 days, with longer stints possible under certain circumstances.

But those limits do not apply to inmates deemed to be violent or hard to manage who are in administrative confinement — a form of isolation that can go on for years, even decades. The status of each inmate in administrative confinement is reviewed every six months, but McKinley Bey charges in his lawsuit that those reviews are a “sham.”

Colorado has banned the use of such indefinite solitary confinement, as has California, which agreed to end it after a legal challenge and a large hunger strike.