Lord Denning was a judge for 38 years before retiring at the age of 83 in 1982. Lord Denning instigated many important concepts that would become pillars of the common law and many more which would ultimately be rejected in the House of Lords (such as the doctrine of fundamental breach). He also made some famous (and infamous) decisions in his court over his long career, and is regarded as somewhat of a legend amongst law students for his witty, no nonsense judgments.
Denning was called to the English bar in 1923, took silk in 1938 and was appointed a High Court judge and knighted in 1944. Only four years later, he was appointed a Lord Justice of Appeal, as well as a Privy Councillor, and in 1957 he became a Lord of Appeal in Ordinary with a life peerage as Baron Denning, of Whitchurch in the County of Southampton. He also served as Master of the Rolls from 1962 to 1982, later receiving the Order of Merit in 1997 in recognition of his distinguished career. He first married in 1932. His wife Mary died nine years later of tuberculosis. He remarried in 1945 to Joan, who died in 1992.
Denning spent twenty years as the Master of the Rolls, presiding over the Civil Division of the Court of Appeal, after five years as a Law Lord, shifting to the Court of Appeal at his request because he was happier with that post than one in the more senior court. Court of Appeal judges sit in threes, and the Lords in fives (or more), so it was suggested that to get his way in the Court of Appeal Denning only had to persuade one other judge whereas in the House of Lords it was at least two. The other 'benefit' of the Court of Appeal is that it hears more cases than the House of Lords, and so has a greater effect on the law. During his twenty years as Master of the Rolls, Denning could choose both which cases he heard, and the judges with whom he sat. Therefore, on most issues, he effectively had the last word; comparatively few cases went on to the House of Lords, Britain's highest court of law. Of his move down the legal hierarchy, Denning quipped, "To most lawyers on the bench, the House of Lords is like heaven. You want to get there someday — but not while there is any life in you."
Denning was especially known for challenging the principle of stare decisis (binding judicial precedent) during his tenure in the Court of Appeal. Although the Civil Division of the Court of Appeal is bound by its own past decisions, with a few exceptions set out in Young v Bristol Aeroplane Co Ltd, Denning argued that as this rule had been set by the Court of Appeal, they could change it. In Gallie v Lee, he stated: "It was a self-imposed limitation and we who imposed it can also remove it." The other judges on the Court of Appeal did not agree; in the same case Russell LJ stated: "The availability of the House of Lords to correct errors in the Court of Appeal makes it, in my view, unnecessary for the court to depart from its existing discipline." In 1979, Denning was part of a panel of judges on Davis v Johnson who refused to follow a precedent set by the Court of Appeal on the statutory interpretation of the Domestic Violence and Matrimonial Proceedings Act 1976. The case went to the House of Lords, who despite agreeing with the new interpretation, "expressly, unequivocally and unanimously reaffirmed the rule in Young v Bristol Aeroplane". Notwithstanding the practical progression of the law reflected in Denning's decisions, his judicial activism has led to severe criticism in some quarters, largely on the basis that such refusal to follow precedent undermined the rule of law and produced uncertainty in the legal system.
In 1963, Denning was appointed by then Prime Minister Harold Macmillan to look into the role of the police and security services in the Profumo affair. However, much of his report was devoted to an investigation of Stephen Ward, a man whom Denning alleged had catered for the "perverted tastes" of others. However, Ward was a relatively minor player in the affair — his only relation to it was in introducing the then Secretary of State for War John Profumo to Christine Keeler, with whom Profumo subsequently became intimately involved. Conspiracy theorists have insinuated that Denning was involved in a cover-up to protect members of the establishment — allegedly including members of the royal family — from being pinned as the culprits.
Although he was the last serving British judge not bound by a mandatory retirement age, he was nonetheless forced to retire after he made remarks interpreted as racially insensitive, though generally understood not to have indicated such feelings. He delivered over 2000 reported judgments and gave more lectures than any other judge.
Denning's 1982 book What Next in the Law was his downfall. In it, he seemed to suggest some members of the black community were unsuitable to serve on juries, and that immigrant groups may have had different moral standards to native Englishmen. His remarks followed a trial over the St Pauls riot in Bristol. Two jurors on the case threatened to sue him, although some scholars have pointed out that his attitudes were not far out of line with opinions in the right-wing press of the day, and may have been taken out of context somewhat. Nonetheless, Lord Denning was forced to back down and avoided further conflict by apologising. He then announced he would be retiring. Later editions of the book assert Denning's commitment to representative juries and diversity.
One of Denning's most influential decisions in torts was his well articulated opinion regarding relational economic loss in Spartan Steel and Alloys Ltd v. Martin & Co. Ltd,  3 All E.R. 557 (C.A.). While his fellow judges, Lawton LJ (concurring) and Edmund Davies LJ (dissenting), based their rulings on stare decisis and general tort principles (respectively). Denning based his judgment on a thorough analysis of relevant policy factors.
If the six men win, it will mean that the police are guilty of perjury, that they are guilty of violence and threats, that the confessions were invented and improperly admitted in evidence and the convictions were erroneous... This is such an appalling vista that every sensible person in the land would say that it cannot be right that these actions should go any further.He also commented that "We shouldn't have all these campaigns to get the Birmingham Six released if they'd been hanged. They'd have been forgotten and the whole community would have been satisfied." The men's convictions were overturned in 1991, after it was shown that the police had indeed done all the things Denning described, and he admitted that the West Midlands Police force had "let us all down". This case also highlighted a major flaw in English judicial independence in that it is very difficult to reverse or alter a ruling.
A number of Denning's decisions during the 1970s and early 1980s were adverse to trade unions. Critics argued that these judgements reflected his personal hostility to unions, reflected in a 1979 statement that "The greatest threat to the rule of law today is posed by the big trade unions".
The world renowned High Trees case: Central London Property Trust Ltd v. High Trees House Ltd  K.B. 130, was a milestone in English contract law and made Denning's name early on in his career as an innovator in legal reasoning. The case is said to have revived the doctrine of equitable estoppel or 'promissory estoppel'. However, Denning's doctrine has been criticised by some legal academics, who argue that he paid little regard to the existing law and that the doctrine is the result of his attempt to find a resolution that equated to his personal notion of "justice." Other legal academics and jurists (such as Roderick Meagher, William Gummow and John Lehane) have defended High Trees as being founded on conventional equitable principles drawn from 19th Century cases such as the House of Lords decision in Hughes v Metropolitan Railway Co. (1877) 2App Cas 439 and the English Court of Appeal in Birmingham & District Land Co v London & North Western Railway (1888) 40 Ch D 268. The doctrine rediscovered by Lord Denning has been applied throughout the common law world.
Even in rather mundane cases, Denning was able to see matters from a realistic, common-sense perspective, often that of the man-on-the-street, which gave his opinions a "real-world" application. For instance, in Thornton v Shoe Lane Parking  1 All ER 686 (CA), the plaintiff drove to the defendant's car park and was given a ticket by an automatic machine, which stated that it was issued subject to conditions displayed inside the car park. The conditions inside the car park were in small print, and one of them excluded liability for damages to vehicles or injury to customers. The plaintiff was injured due partly to the defendant's negligence. The plaintiff was not held to be bound by the notice displayed inside the premises, as its existence was not made aware to the defendant prior to paying. Denning also stated that this particular clause was so wide and destructive of rights that "In order to give sufficient notice, it would need to be printed in red ink with a red hand pointing to it - or something equally startling.". This "red hand rule" was first introduced by Denning in J. Spurling Ltd v Bradshaw .
In the last major case in which Denning gave judgment, George Mitchell (Chesterhall) Ltd v Finney Lock Seeds Ltd  3 WLR 1036 (CA), in September 1982, he referred to freedom of contract in the area of disclaimer exemption clauses as an "idol": "The judges knelt down, and worshipped it but they concealed, under their cloaks a secret weapon. They used it to stab the idol in the back. This weapon was called "the true construction of the contract." He went on: "They used the weapon of true construction, of the contract so as to depart from the natural meaning of the words of the exemption clause and to put upon them a strained and unnatural construction , . ." Denning, of course, intended no attack on the sanctity of contract in general terms; he was talking only of exemption clauses. His words are candid; but the process which he describes might be regarded by a layman as cheating because it is to do one thing and to call it another.
The University of Buckingham's Law School organised a Symposium whereby each of the major area of law that Denning has had a profound influence on was discussed and debated. Each topic of discussion was chaired by someone with experience in that scope. E.g. The Rt. Hon. Lord Nolan on Public Inquiries. (Other Chairmen included Lords Woolf, Slynn). Afterwards the Law School's Law Society organised a Charity Dinner in which many of the guest speakers and attendees of the Symposium attended. The guest speaker was the then Vice-Chancellor of the Supreme Court, The Rt. Hon. Sir Richard Scott, now Lord Scott of Foscote, a Law Lord.
Lord Denning was more than simply a learned and gifted jurist. His judgments were sharp, pithy and full of mischief. Perhaps his most famous case was Miller v. Jackson (1977) Q.B. 966, 976, or as it is far better known, The Cricket Case, with its well-known lyrical opening to Lord Denning's judgment, the first paragraph of which reads:
In summertime village cricket is the delight of everyone. Nearly every village has its own cricket field where the young men play and the old men watch. In the village of Lintz in County Durham they have their own ground, where they have played these last 70 years. They tend it well. The wicket area is well rolled and mown. The outfield is kept short. It has a good club house for the players and seats for the onlookers. The village team play there on Saturdays and Sundays. They belong to a league, competing with the neighbouring villages. On other evenings after work they practise while the light lasts. Yet now after these 70 years a judge of the High Court has ordered that they must not play there any more. He has issued an injunction to stop them. He has done it at the instance of a newcomer who is no lover of cricket. This newcomer has built, or has had built for him, a house on the edge of the cricket ground which four years ago was a field where cattle grazed. The animals did not mind the cricket. But now this adjoining field has been turned into a housing estate. The newcomer bought one of the houses on the edge of the cricket ground. No doubt the open space was a selling point. Now he complains that when a batsman hits a six the ball has been known to land in his garden or on or near his house. His wife has got so upset about it that they always go out at week-ends. They do not go into the garden when cricket is being played. They say that this is intolerable. So they asked the judge to stop the cricket being played. And the judge, much against his will, has felt that he must order the cricket to be stopped: with the consequence, I suppose, that the Lintz Cricket Club will disappear. The cricket ground will be turned to some other use. I expect for more houses or a factory. The young men will turn to other things instead of cricket. The whole village will be much the poorer. And all this because of a newcomer who has just bought a house there next to the cricket ground.
Denning was a serious and committed Christian believer. He served as president from 1950-1987 and until his death as patron of the Lawyers’ Christian Fellowship in the United Kingdom. A chapter in his 1953 book The Changing Law continues to be distributed as an evangelistic booklet by LCF under the title The Influence of Religion. That essay concludes with these lines: "If religion perishes in the land, truth and justice will also. We have already strayed too far from the path of our fathers. Let us return to it, for it is the only thing that can save us."
Other famous and infamous quotes include:
The Birmingham Six
"We shouldn't have all these campaigns to get them released".
The Profumo scandal inquiry
"I have had to be a detective, inquisitor, advocate and judge and it has been difficult to combine them."
Reversals of his rulings
"It's not the first time and probably won't be the last".
"Parliament does it too late".
A career in law
"I was ambitious and saw it as the best way to advancement".
"Without religion, no morality; without morality, no law."
Some persons, who would otherwise be good and worthy citizens, are deliberately breaking the law."
"I have all the Christian virtues - except resignation".
"You can do good work after 75. I think I gave some of my judgments of greatest value after 75."
"By eating plain English food. I don't want any of that French stuff."
His chosen epitaph
"Remembrance of me in good works, that is how I should like to be remembered."