A sexual psychopath committed pursuant to RCW
71.06.060 shall be retained by the superintendent of the institution involved until in the superintendent's opinion he or she is safe to be at large, or until he or she has received the maximum benefit of treatment, or is not amenable to treatment, but the superintendent is unable to render an opinion that he or she is safe to be at large. Thereupon, the superintendent of the institution involved shall so inform whatever court committed the sexual psychopath. The court then may order such further examination and investigation of such person as seems necessary, and may at its discretion, summon such person before it for further hearing, together with any witnesses whose testimony may be pertinent, and together with any relevant documents and other evidence. On the basis of such reports, investigation, and possible hearing, the court shall determine whether the person before it shall be released unconditionally from custody as a sexual psychopath, released conditionally, returned to the custody of the institution as a sexual psychopath, or transferred to the department of corrections to serve the original sentence imposed upon him or her. The power of the court to grant conditional release for any such person before it shall be the same as its power to grant, amend, and revoke probation as provided by chapter
9.95 RCW. When the sexual psychopath has entered upon the conditional release, the indeterminate sentence review board shall supervise such person pursuant to the terms and conditions of the conditional release, as set by the court: PROVIDED, That the superintendent of the institution involved shall never release the sexual psychopath from custody without a court release as herein set forth.