A/HRC/33/66 C. Action taken on communications 17. In the light of the information obtained, the Working Group shall take one of the following measures: (a) If the person has been released, for whatever reason, following the referral of the case to the Working Group, the case is filed. The Working Group reserves the right to render an opinion, on a case-by-case basis, whether or not the deprivation of liberty was arbitrary, notwithstanding the release of the person concerned; (b) If the Working Group considers that the case is not one of arbitrary detention, it shall render an opinion to that effect. The Working Group can also make recommendations in this case if it considers it necessary; (c) If the Working Group considers that further information is required from the Government or from the source, it may keep the case pending until that information is received; (d) If the Working Group considers that the arbitrary nature of the detention is established, it shall render an opinion to that effect and make recommendations to the Government. 18. The opinions rendered by the Working Group shall be transmitted to the Government concerned. Forty-eight hours after their transmittal, they shall be communicated to the source. An advance unedited version of the opinion will be published online once the source has been notified. 19. The opinions rendered by the Working Group shall be brought to the attention of the Human Rights Council in its annual report. 20. Governments, sources and other parties should inform the Working Group of the follow-up action taken on the recommendations made by the Working Group in its opinion. This will enable the Working Group to keep the Human Rights Council informed of the progress made and of any difficulties encountered in implementing the recommendations, as well as of any failure to take action. D. Procedure for review of opinions 21. In exceptional circumstances, the Working Group may proprio motu reconsider its opinions if it becomes aware of new facts that, if known at the time of the decision, would have led the Working Group to a different outcome. The Working Group may also reconsider its opinions at the request of the Government concerned or the source under the following conditions: (a) If the facts on which the request is based are considered by the Working Group to be entirely new and such as to have caused the Working Group to alter its decision had it been aware of them; (b) If the facts had not been known or had not been accessible to the party originating the request; (c) In a case where the request comes from a Government, on condition that the latter has observed the time limit for reply referred to in paragraphs 15-16 above; GE.16-11947 5