Kenneth Diplock, Baron Diplock

William John Kenneth Diplock, Baron Diplock, PC (8 December 1907 – 14 October 1985[1]) was a British judge and successively a Justice of the High Court in England and Wales and a Lord Justice of Appeal before being created a Law Lord.[2]

The Right Honourable Lord Diplock
Lord of Appeal in Ordinary
In office 30 September 1968 – 14 October 1985
Monarch	Elizabeth II
Personal details
Born	(1907-12-08)8 December 1907
Died	14 October 1985(1985-10-14) (aged 77)

Early life

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He was born in Croydon, the second child of Irish solicitor Herbert Diplock and his wife Christine. He attended Whitgift School in Croydon and University College, Oxford, where he read chemistry and graduated with a second-class degree.[3] He later become an Honorary Fellow in 1958.[4]

Career

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Diplock was called to the Bar by the Middle Temple in 1932. He left practice in 1939 to serve in the war; in 1941 he joined the Royal Air Force, in which he reached the rank of squadron leader.[3] From 1939 to 1948, he served as secretary to the Master of the Rolls, Lord Greene.[3]

He subsequently returned to practice in 1945; he was made a King's Counsel (KC) in 1948, at the age of 41. In 1956, he was appointed to the High Court.[4]and then promoted the Court of Appeal in 1961.

He became a Lord of Appeal in Ordinary (Law Lord) on 30 September 1968[1] and was elevated as a life peer with the title Baron Diplock, of Wansford in the County of Huntingdon and Peterborough to the House of Lords.[5][6]He became the senior Law Lord upon the retirement of Lord Wilberforce in 1982. He resigned his seniority in October 1984 but remained a Law Lord until his death the following year.

As Lord Diplock, he chaired a commission set up in 1972 to consider legal measures against terrorism in Northern Ireland, which led to the establishment of the juryless Diplock courts with which his name is now often associated.

At the time of his death, Lord Diplock was the longest serving Law Lord.[1]

Personal life

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He married Maraget Sarah Atcheson in 1938; they had no children.[7][3]

Contributions to legal thought

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He made many contributions to legal thought and pushed the law in new and unique directions, not least UK courts without juries ('Diplock courts)'.[8] His rulings, especially those on administrative law, are often considered as authoritative not only in England but across the Commonwealth and even in the United States, where he has been cited by the Supreme Court.[9][10]

Examples include Council of Civil Service Unions v Minister for the Civil Service [1984] UKHL 9 or R (National Federation of Self-Employed and Small Businesses Ltd) v Inland Revenue Commissioners [1982] A.C. 617, on grounds of review and locus standi respectively.

The current typology of grounds for judicial review is owing to Lord Diplock.

• Procedural impropriety[11]
• Nemo judex (Bias rule)[12]
• Audi alteram partem (Hearing rule)[13]
• Illegality[14]
• Ultra vires
• Simple ultra vires
• Extended ultra vires
• Procedural ultra vires
• Fettering
• Irrationality[14]
• Wednesbury irrationality
• Lack of proportionality
• Innominate Terms[15]
• Primary and Secondary Obligations[16]

Notable judgments

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• Hong Kong Fir Shipping Co Ltd v Kawasaki Kisen Kaisha Ltd [1962] 2 QB 26[4]
• Harvela Investments Ltd v Royal Trust of Canada (CI) Ltd [1986] AC 207[4]
• Council of Civil Service Unions v Minister for the Civil Service [1985] AC 374
• Whitehouse v Lemon; Whitehouse v Gay News Ltd [1979] 2 WLR 281
• O'Reilly v Mackman [1983] 2 AC 237
• American Cyanamid Co v Ethicon Ltd [1975] A.C.396 HL
• Catnic Components Ltd v Hill & Smith Ltd (1982)

See also

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• Judicial review in English law
• Air New Zealand Flight 901

References

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