(1) No inmate shall be held in restrictive housing unless done in the least restrictive manner consistent with maintaining order in the facility and pursuant to rules and regulations adopted and promulgated by the department pursuant to the Administrative Procedure Act.
(2) The department shall adopt and promulgate rules and regulations pursuant to the Administrative Procedure Act establishing levels of restrictive housing as may be necessary to administer the correctional system. Rules and regulations shall establish behavior, conditions, and mental health status under which an inmate may be placed in each confinement level as well as procedures for making such determinations. Rules and regulations shall also provide for individualized transition plans, developed with the active participation of the committed offender, for each confinement level back to the general population or to society.
(3) On and after March 1, 2020, no inmate who is a member of a vulnerable population shall be placed in restrictive housing. In line with the least restrictive framework, an inmate who is a member of a vulnerable population may be assigned to immediate segregation to protect himself or herself, staff, other inmates, or inmates who are members of vulnerable populations pending classification. The department shall adopt and promulgate rules and regulations pursuant to the Administrative Procedure Act regarding restrictive housing to address risks for inmates who are members of vulnerable populations. Nothing in this subsection prohibits the department from developing secure mental health housing to serve the needs of inmates with serious mental illnesses as defined in section 44-792, developmental disabilities as defined in section 71-1107, or traumatic brain injuries as defined in section 79-1118.01 in such a way that provides for meaningful access to social interaction, exercise, environmental stimulation, and therapeutic programming.
(4) For purposes of this section, member of a vulnerable population means an inmate who is eighteen years of age or younger, pregnant, or diagnosed with a serious mental illness as defined in section 44-792, a developmental disability as defined in section 71-1107, or a traumatic brain injury as defined in section 79-1118.01.