; or (B) a facility under contract with the United States Marshals Service to provide housing for inmates in Federal custody. (5) Disciplinary hearing officer The term disciplinary hearing officer means an individual who— (A) in the case of— (i) the Bureau of Prisons or the United States Marshals Service, is an employee who is a supervisory or administrative officer who is employed in the office of the regional director, central office, or district office; or (ii) a facility that contracts with the Bureau of Prisons or the United States Marshals Service, is the designee of the Director of the Bureau of Prisons or the Director of the United States Marshals Service; and (B) is responsible for conducting disciplinary hearings for which solitary confinement may be a sanction, as described in section 541.8 of title 28, Code of Federal Regulations, or any successor thereto. (6) Disciplinary segregation The term disciplinary segregation means a form of separation from the general population of a facility imposed only by a disciplinary hearing officer as a response to an inmate committing a significant and serious disciplinary infraction. (7) Intellectual disability The term intellectual disability means a mental impairment characterized by significant limitations in both intellectual functioning and adaptive behavior. (8) Mental illness The term mental illness means a diagnosable mental, behavioral, or emotional disorder that— (A) is of sufficient duration to meet diagnostic criteria within the most recent edition of the Diagnostic and Statistical Manual of Mental Disorders published by the American Psychiatric Association