DOCTRINE OF PRECEDENT - LAW MAKING POTENTIAL
THE JUDGES' ROLE IN PRECEDENT
The old view of the judges' role was that they were merely 'declaring' the existing law (the 'declaratory theory'). Lord Esher stated in Willis v Baddeley  2 QB 324:
"There is ... no such thing as judge-made law, for the judges do not make the law, though they frequently have to apply existing law to circumstances as to which it has not previously been authoritatively laid down that such law is applicable."
The modern view is that judges do make law. Lord Radcliffe said (Not in Feather Beds, p215, 1968):
"... there was never a more sterile controversy than that upon the question whether a judge makes law. Of course he does. How can he help it?"
The reality is that judges are continually applying the existing rules to new fact situations and thus creating new laws.
THE POSITION OF THE HOUSE OF LORDS
In the mid-nineteenth century the House of Lords developed the practice that it would be bound by its own decisions. This was reaffirmed in London Tramways Co v London County Council  AC 375. The House of Lords felt that decisions of the highest appeal court should be final in the public interest so that there would be certainty in the law and an end to litigation. However, this practice was criticised from the 1930s. Some of the Law Lords said that the rule did not produce the desired certainty in the law and it had become too rigid (eg, Lord Wright, Lord Denning and Lord Reid).
Nevertheless, the practice was not changed until 1966 by Lord Gardiner LC. The practice statement was accompanied by a press release, which emphasised the importance of and the reasons for the change in practice:
It would enable the House of Lords to adapt English law to meet changing social conditions.
It would enable the House to pay more attention to decisions of superior courts in the Commonwealth.
The change would bring the House into line with the practice of superior courts in many other countries. In the USA, for example, the US Supreme Court and state supreme courts are not bound by their own previous decisions.
A. Paterson's survey of nineteen Law Lords active between 1967 and 1973 found that at least twelve thought that the Law Lords had a duty to develop the common law in response to changing social conditions (A. Paterson, The Law Lords, 1982).
EXAMPLES OF JUDICIAL ACTIVISM & SOCIAL CHANGE
1. In Herrington v British Railways Board  AC 877, the House of Lords overruled (or at least, modified) Addie v Dumbreck  AC 358. In Addie, the House of Lords had held that an occupier of premises was only liable to a trespassing child who was injured by the occupier intentionally or recklessly. In Herrington, their Lordships held that a different approach was appropriate in the changed social and physical conditions since 1929. They propounded the test of 'common humanity' which involves an investigation of whether the occupier has done all that a humane person would have done to protect the safety of the trespasser.
2. In Miliangos v George Frank (Textiles) Ltd  AC 443, the House of Lords overruled Re United Railways  AC 1007. In Re United Railways, it had been held that damages in an English civil case could only be awarded in sterling. In Miliangos, the House of Lords held that damages can be awarded in the currency of any foreign country specified in the contract. A new rule was needed because of changes in foreign exchange conditions, and especially the instability of sterling, since 1961.
3. In R v Howe  2 WLR 568, the House of Lords overruled DPP for N. Ireland v Lynch  AC 653, and decided that the defence of duress is not available to a person charged with murder, whether as a principal or as a secondary party. In Lynch, the House of Lords had held that duress was available as a defence to a person who had participated in a murder as an aider and abettor. In Howe, their Lordships desired to restore this part of the criminal law to what it was generally understood to be prior to Lynch, even though to do so would produce the illogical result that, whilst duress is a complete defence to all crimes less serious than murder, it is not even a partial defence to a charge of murder itself.