Breach of confidence in English law

The "three traditional requirements of the cause of action for breach of confidence"[2]^:[19] were identified by Robert Megarry in Coco v A N Clark (Engineers) Ltd (1968) in the following terms:[3]

In my judgment, three elements are normally required if, apart from contract, a case of breach of confidence is to succeed. First, the information itself, in the words of Lord Greene, M.R. in the Saltman case on page 215, must "have the necessary quality of confidence about it." Secondly, that information must have been imparted in circumstances importing an obligation of confidence. Thirdly, there must be an unauthorised use of that information to the detriment of the party communicating it.

The modern English law of confidence stems from the judgment of the Lord Chancellor, Lord Cottenham,[4] in which he restrained the defendant from publishing a catalogue of private etchings made by Queen Victoria and Prince Albert (see Prince Albert v Strange).

However, the jurisprudential basis of confidentiality remained largely unexamined until the case of Saltman Engineering Co. Ltd. v Campbell Engineering Co. Ltd.,[5] in which the Court of Appeal upheld the existence of an equitable doctrine of confidence, independent of contract.

In Attorney-General v Observer Ltd (1990) – the Spycatcher case – Lord Goff of Chieveley identified three limitations to the doctrine:[6]^:282

To this broad general principle, there are three limiting principles to which I wish to refer. The first limiting principle (which is rather an expression of the scope of the duty) ... is that the principle of confidentiality only applies to information to the extent that it is confidential ... once it has entered what is usually called the public domain ... then, as a general rule, the principle of confidentiality can have no application to it ... The second limiting principle is that the duty of confidence applies neither to useless information, nor to trivia ... The third limiting principle is of far greater importance. It is that, 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.

The incorporation into domestic law of Article 8 of the European Convention on Human Rights by the Human Rights Act 1998 has since had a profound effect on the development of the English law of confidentiality. Article 8 provides that everyone has the right to respect for his private and family life, his home and his correspondence. In Campbell v MGN Ltd,[2] the House of Lords held that the Daily Mirror had breached Naomi Campbell’s confidentiality rights by publishing reports and pictures of her attendance at Narcotics Anonymous meetings.

Although the court divided 3–2 as to the result of the appeal and adopted slightly different formulations of the applicable principles, there was broad agreement that, in confidentiality cases involving issues of privacy, the focus shifted from the nature of the relationship between claimant and defendant to (a) an examination of the nature of the information itself and (b) a balancing exercise between the claimant's rights under Article 8 and the defendant's competing rights (for example, under Article 10, to free speech).

• Lennon v News Group Newspapers Ltd (1978) FSR 573
• Commonwealth v John Fairfax & Sons [1980] HCA 44, (1980) 147 CLR 39
• Moorgate Tobacco Co Ltd v Philip Morris Ltd (No 2) [1980] HCA 44, (1984) 156 CLR 414, 438
• Smith Kline & French Laboratories (Australia) Ltd v Secretary, Department of Community Services & Health [1991] FCA 150, (1991) 28 FCR 291
• Telstra Corp Ltd v First Netcom Pty Ltd [1997] FCA 860, (1997) 78 ALR 202, 208
• R v Department of Health; Ex parte Source Informatics Ltd [2000] 1 All ER 786
• Attorney General v Observer and Guardian Newspapers Ltd [2011] UKSC 39

• Privacy in English law

• The Law Commission (October 1981). Breach of confidence (PDF). Her Majesty's stationery office. Retrieved 3 December 2017.