Inmates held in solitary confinement at Rikers Island as punishment for violations during previous stints in jail are suing to stop the practice, known as owed time.

A class action lawsuit filed in Southern District federal court Thursday (See Complaint) says inmates are unfairly placed in 23-hour confinement for breaking jailhouse rules in previous detentions, sometimes years earlier. For example, if an inmate is sentenced to a month in solitary confinement but is released or transferred before completing it, he can be forced to serve the remaining time during his next incarceration.