19/09/2019 HCMP2801/2015 THE UNIVERSITY OF HONG KONG v. HONG KONG COMMERCIAL BROADCASTING CO LTD AND ANOTHER 50. The right to prevent disclosure of information imparted in confidence is however not an absolute right. It is a right that admits of exceptions. One of the exceptions is the so-called “public interest defence”. This defence has not, and probably cannot, be precisely defined, and its scope is not entirely clear or settled. In Attorney General v Guardian Newspapers Ltd (No 2), supra, at p 282E, Lord Goff referred to it as the third “limiting principle” in these terms: .. although the basis of the law’s protection of confidence is that there is a public interest that confidences should be preserved and protected by the law, nevertheless that public interest may be outweighed by some other countervailing public interest which favours disclosure. ... It is this limiting principle which may require a court to carry out a balancing operation, weighing the public interest in maintaining the confidence against a countervailing public interest favouring disclosure. 4 Embraced within this limiting principle is, of course, the so called defence of iniquity. In origin, this principle was narrowly stated, on the basis that a man cannot be made ‘the confidant of a crime or a fraud’ ... But it is now clear that the principle extends to matters of which disclosure is required in the public interest ...” 51. A review of the authorities shows that the courts have considered that public interest could require disclosure for the detection or prevention of wrongdoing, prevention of miscarriage of justice, or protection of public health and safety. Toulson & Phipps, Confidentiality, in a passage cited without disapproval by Robert Walker LJ in London Regional Transport v Mayor of London |2003| EMLR 4 at §36, suggests that the question depends on whether there is a “serious risk of public harm” which would be prevented by disclosure. 52. A rule that requires a simple uncalibrated weighing exercise will hardly offer guidance to parties and the courts. A defence that is too broad and ill-defined may weaken the ability of those who enter into a relationship or agreement of confidence to rely on the principle of confidentiality. Indeed, in Australia, which adopts a narrower public interest defence, it has been said by Gummow J in Smith Kline and French Laboratories (Australia) Ltd v Department of Community Services and Health [1990] FSR 617, 663, that unless kept within strict limits, the defence becomes: . not so much a rule of law as an invitation to judicial idiosyncracy by deciding each case on an ad hoc basis as to whether, on the facts overall, it is better to respect or to override the obligation of confidence.” 4 https: //legalref.judiciary.hk/Irs/common/ju/ju_frame.jsp? DIS=101619&currpage=T 17/33