Criminal law / Necessity
In 1884 a court had to say whether a starving man may kill to live. R v Dudley and Stephens decided that necessity was no defence to murder. This page tells the case as a story, then follows how the law moved.
Built by a law student, with the students who use it.
The yacht Mignonette went down on 5 July 1884, about 1,600 miles from the Cape of Good Hope. Four men were in the lifeboat: Dudley, Stephens, Brooks and Parker, the cabin boy, who was between 17 and 18.
On 25 July, the twentieth day, Dudley killed Parker, with Stephens's assent. Brooks dissented. No lots were drawn. The boy was not consulted and never assented.
Three of them fed on the body. They were picked up on the fourth day after the killing and landed at Falmouth. Dudley and Stephens were tried before Huddleston B at Exeter on 6 November 1884. The special verdict set out the facts and recorded "no greater necessity for killing the boy than any of the other three men".
The question of law was then referred to what Brooke LJ later called "a court of five judges". Those are the facts the judges had. What they made of them is the rest of this page.
Lord Coleridge CJ gave judgment on 9 December 1884. He put the question this way: "the real question in the case, whether killing under the circumstances set forth in the verdict be or be not murder."
The court held that "the prisoners' act in this case was wilful murder, that the facts as stated in the verdict are no legal justification of the homicide".
The death sentence was "afterwards commuted by the Crown to six months' imprisonment."
Lord Coleridge asked who could judge such a necessity, and by what measure.
"Who is to be the judge of this sort of necessity? By what measure is the comparative value of lives to be measured? Is it to be strength, or intellect, or what?"
His second reason was what the principle could be used for once it was admitted.
"it is quite plain that such a principle once admitted might be made the legal cloak for unbridled passion and atrocious crime."
He also said of the court's own position: "We are often compelled to set up standards we cannot reach ourselves, and to lay down rules which we could not ourselves satisfy."
These passages are at (1884) 14 QBD 273, 286 to 288, as Brooke LJ set them out in Re A at page 224.
Four cases, from the lifeboat to a hospital ward. Open each stop to read what happened, what the court did and what it left open.
(1884) 14 QBD 273, Queen's Bench Division, 1884
On the twentieth day in the lifeboat, Dudley killed Parker, the cabin boy, with Stephens's assent. Brooks dissented. No lots were drawn, and the boy was not consulted and never assented.
Lord Coleridge CJ called it "the real question in the case, whether killing under the circumstances set forth in the verdict be or be not murder."
Held: "the prisoners' act in this case was wilful murder, that the facts as stated in the verdict are no legal justification of the homicide".
"To preserve one's life is generally speaking a duty, but it may be the plainest and the highest duty to sacrifice it."
Lord Coleridge CJ
Brooke LJ said in Re A that Dudley, "endorsed though it was by the House of Lords in R v Howe, is not conclusive of the matter".
Lord Coleridge CJ
As the law currently stands in England and Wales, necessity is no defence to murder, and duress is no defence to murder or attempted murder. In Re A the Court of Appeal accepted a necessity argument on unique facts, and confined it to those facts. In R v Hasan [2005] UKHL 22 Lord Bingham restated the duress rule: no defence to murder, to attempted murder, and perhaps to some forms of treason.
In R v Howe [1987] AC 417 the House of Lords held that duress was not available as a defence to murder or to aiding or abetting murder, and in R v Gotts [1992] 2 AC 412 it held, by a majority, that duress is not available on a charge of attempted murder. The Law Commission describes duress as "a full defence to all crimes except murder, attempted murder, possibly some forms of treason and, possibly, conspiracy" (Law Com 304, paragraph 6.5).
The Law Commission describes "two forms of duress: duress by threats and duress of circumstances", with the same general principles (Law Com 304, paragraphs 6.6 to 6.8). Pommell [1995] 2 Cr App R 607 is an example of duress of circumstances. It was a case about possessing a firearm, a retrial was ordered, and it was not a murder case.
The Law Commission also reads Dudley in that light. In footnote 9 of the same report it says the case, "properly analysed, is one of duress of circumstances". That is the Commission's view, not the court's.
In 2006 the Law Commission recommended that duress should be a full defence to murder and attempted murder, with the burden of proof on the defendant (paragraphs 1.56 and 1.57). It described the position then as "At present, however, duress is no defence to murder at all." That recommendation has not become law, and the Law Commission's news release of 14 August 2025 records that the government did not implement most of the report's recommendations.
The Law Commission's review of homicide opened a public consultation on 17 June 2026, which closed on 16 October 2026. Defences are not part of it. The Commission says: "We will hold a public consultation on defences and sentencing in future". A consultation changes nothing by itself, so the rule above is still the rule today.
In Re A the Court of Appeal heard, in September 2000, a case about conjoined twins, Jodie and Mary. They were "joined at the pelvis and each had her own brain, heart and lungs". Without an operation "both would die within a few months of their birth". If they were separated, Jodie "would have a life which was worthwhile although M would die within minutes." Their parents refused consent on religious grounds. The court held that the operation "could be lawfully carried out", and the three judges reached that result by three routes.
"the carrying out of the operation will be justified as the lesser evil and no unlawful act would be committed" (pages 203 to 204). He also reasoned by analogy with self-defence.
Brooke LJ set out three requirements he took from Sir James Stephen: "(i) the act is needed to avoid inevitable and irreparable evil; (ii) no more should be done than is reasonably necessary for the purpose to be achieved; (iii) the evil inflicted must not be disproportionate to the evil avoided." He held that all three were met (pages 239 to 240).
"Mary's death would not be the purpose or intention of the surgery, and she would die because tragically her body, on its own, is not and never has been viable." (page 259).
Ward LJ then limited what the decision stands for: "Lest it be thought that this decision could become authority for wider propositions, such as that a doctor, once he has determined that a patient cannot survive, can kill the patient, it is important to restate the unique circumstances for which this case is authority." (pages 204 to 205).
Re A did not overturn Dudley and Stephens. Ward LJ's warning is the court's own limit on what it decided.
In Attorney General v Whelan [1934] IR 518, at page 524, the court said in passing (obiter) that "the commission of murder is a crime so heinous that [it] should not be committed even for the price of life and in such a case the strongest duress would not be any justification". The case itself was about receiving stolen money.
The Law Reform Commission made recommendations in LRC 95-2009, published in December 2009. At paragraph 7.43 it recommended that duress be "generally available as a defence, but not in the case of treason, murder or attempted murder". At paragraph 7.45 it recommended that necessity "should continue to be developed on a case-by-case basis".
They are recommendations, not the law, unless and until they are enacted.
Queen's Bench Division, 1884. (1884) 14 QBD 273
The lifeboat case: the killing of the cabin boy was held to be wilful murder.
House of Lords, 1987. [1987] AC 417
Duress was held not to be a defence to murder or to aiding or abetting murder.
House of Lords, 1992. [1992] 2 AC 412
By a majority, duress was held not to be a defence to attempted murder.
Court of Appeal, 2000. [2001] Fam 147
An operation to separate conjoined twins, ending the life of one, was held lawful.
Open a case to read the full analysis, then save it to your Library from there.
Doctors want to separate conjoined twins. Without surgery both will die, and the operation will end the life of the weaker twin. Build the argument on whether necessity can be a defence to murder in England and Wales.
LexCases will turn this into a search and show you the cases on each side.
Check every case against the report before you rely on it in formal work. This page describes the law as it currently stands, and the law moves.
On this page