“Such a precondition would impose upon the exercise of the governor’s discretion, in his task of maintaining discipline, a fetter which is not expressly imposed by the prison rules and which, in our judgment, is not only not implicitly required by those rules, upon their proper construction, but seems to us to be contrary to the fullness of discretion which in such matters those rules intend a prison governor to have.”
“In this case Mr Sedley [counsel for the Claimant] acknowledged that there could not be an unqualified obligation in all cases upon the governor to allow the right to be heard. There may be cases of urgency. We would add that there may be difficulty in disclosing the reasons, or part of them, if, for example, the intention to segregate is based upon information obtained as to threatened misconduct, such as violence against another prisoner. Giving detailed notice of the grounds might well indicate to the prisoner the source of the information and thereby create the risk of an immediate retaliation against the giver of the information … In another case a governor might reasonably claim that he could not sensibly disclose the reasons for his intended decision, or some part of those reasons, because of the need not to reveal either the source of the information or that certain facts are known to the prison department.”