Was the Nuremberg tribunal a case of “victors’ justice”? That’s the claim that has dogged the International Military Tribunal since it since it first sat 75 years ago tomorrow. It’s a charge that was levelled by Hermann Goering, a defendant at Nuremberg and one of the principal architects of the Nazi regime. But any suggestion that the tribunal was operating under laws that were simply invented by the Allies after their defeat of Nazi Germany is one that was comprehensively demolished during two lectures held by Gray’s Inn during the past week.

The first was delivered by Sir Stephen Irwin, this year’s treasurer — or elected head — of Gray’s Inn, one of the four inns of court (and the one of which I am an honorary member). He traced the concept of natural law back to Roman times, quoting Cicero’s argument that not even a dictator could put a citizen to death without trial. Moving to medieval Europe, Irwin noted that Shakespeare, in Henry V, had the Welsh captain Fluellen say it was “expressly against the law of arms” for the French army to have killed the boys who were looking after the baggage at Agincourt.

Hugo Grotius, who laid the foundations of international law, argued in 1625 that might was not always right: “just as even God cannot cause that two times two should not make four, so He cannot cause that which is intrinsically evil to be not evil.”

But, as Irwin explained, public awareness of mass slaughter in the 19th century — in conflicts such as the American civil war and the Crimean war — led to the creation of the Red Cross in 1863 and the adoption of the first Geneva convention in 1864. Even warfare now had its limits.

Moving on to the 20th century, it was FE Smith, attorney general during the first world war and lord chancellor shortly after it, who argued in support of international criminal law and the creation of a tribunal to enforce it. “It is better to harness your wagon to a star than to a machine-gun,” he wrote, “though a knowledge of the one may be very useful as a means of attaining to the other.” Smith, who was later to become the Earl of Birkenhead, supported the idea of putting the former Kaiser Wilhelm II on trial after the war.

The story was taken up by Sir Christopher Greenwood GBE CMG QC, delivering the Birkenhead lecture that Gray’s Inn has named after one of its most celebrated members. He suggested that Smith had proposed an international court as a counterpart to the popular “hang the Kaiser without a trial” sentiment. In the end, though, there was neither a trial nor a hanging: the ex-emperor fled to the Netherlands and the Dutch refused to extradite him.

“After that,” said Greenwood, “the trial process largely collapsed. There were a handful of trials in Germany itself, but none of them really came to anything.”

By then, though, the idea of war crimes trials had become firmly established. At the Versailles peace conference in 1919, advice was sought by the Allies from a multi-national commission of legal experts. The lawyers found no precedent for charging an individual with the crime of aggression — starting the war in the first place. But they endorsed the idea of charging individuals — even a former head of state — with violating customary laws that applied during the war itself. And the political leaders would have gone further: article 227 of the Versailles treaty publicly arraigned “William II of Hohenzollern, formerly German Emperor, for a supreme offence against international morality and the sanctity of treaties”.

On, then, to the Second World War and its aftermath. There might have been a series of drumhead tribunals, with only the most perfunctory consideration of guilt or innocence before the summary execution of leading Nazis. Churchill and Roosevelt “toyed with the idea,” said Greenwood. But, as Irwin reminds us, it was Roosevelt’s successor as US president, Harry S Truman, who insisted on due process.

An agreement signed in August 1945 created a tribunal with members a drawn from the victorious Allies: the UK, the US, France and the USSR. It was the first international criminal court in history. Article 6 of the tribunal’s charter gave it power to try and punish individuals with responsibility for:

• Crimes against peace — which includes planning or waging a war of aggression or “participation in a common plan or conspiracy” to do so; and

• War crimes — which means “violations of the laws and customs of war”; and

• Crimes against humanity — such as murder, enslavement and “other inhumane acts committed against any civilian population”.

The first category encompassed counts one and two of the indictment: participation in a common plan or conspiracy; and crimes against peace itself. The remaining two charges were crimes and crimes against humanity. Most — but not all — of the 21 men in the dock at the first Nuremberg trial were charged with all four counts.

As Greenwood explained, the concept of war crimes was intended to protect the population of one belligerent state from the forces of a rival belligerent state. It did not protect the population of a state from its own government. So Germany’s attempt to exterminate its own Jewish population could not be classified as a war crime — only as a crime against humanity. By contrast, Germany’s attempt to wipe out the Jewish population of France was both.

War crimes were well established in customary international law and had been codified in written agreements. But the same could not be said in 1945 for crimes against humanity: the concept had been developed little more than a week before the charter was agreed — in a conversation between Hersch Lauterpacht, the leading international lawyer, and Robert Jackson, the chief US prosecutor, over tea in Cambridge.

The Nuremberg tribunal was obviously uneasy about the charge, Greenwood noted. “It decided that crimes against humanity had to be linked to the execution of the war itself.” Persecution of Jews and others between 1932 and 1939 were largely excluded. However, Julius Streicher, editor of an antisemitic propaganda-sheet called Der Stürmer, was executed for crimes against humanity — even though he had not been allowed anywhere near the military decision-making process during the war.

“But if there was some difficulty with the concept of crimes against humanity,” said Greenwood, “there was a great deal more difficulty with the notion of crimes against the peace and the common plan or conspiracy… No one was convicted on count one for conspiracy unless they were also convicted on count two of the crime of actually waging aggressive war.” Of the defendants in the dock at the first Nuremberg trial, 13 were acquitted of conspiracy. Three were found not guilty on all counts.

As Greenwood explained, the judges were concerned that crimes against the peace might amount to retrospective criminal law. All civilised nations respect the principle of nulla poena sine lege, which can be translated as “no punishment without pre-existing law”.

Can one really argue that Streicher’s vile incitement to murder should not have been punished because it did not amount to a crime under the laws of Nazi Germany? Or that Baldur von Shirach should not have been convicted of crimes against humanity, and imprisoned for 20 years, because there was no law against using slave labour or deporting Viennese Jews to German death camps?

Greenwood had no doubt:

One of the reasons for nulla poene sine lege is nobody should be put in the position of acting in good faith, thinking that what they are doing is legal, only to have it treated as criminal afterwards. But it’s hard to see how anyone involved in the sort of activity that led to convictions for crimes against humanity could ever have thought that.

Answering questions afterwards, Greenwood refused to be deflected from his view that Nuremberg was not an example of “victors’ justice”. What about the Allied bombing of Dresden? There was a word of difference, he replied. Nobody should be proud of what happened there but there was no comparison with the running of the concentration camps, the massacres of prisoners of war and atrocities of that kind.

And what about the rocket scientist Wernher von Braun, one of around 1,600 German scientists, engineers and technicians who were freed to work in the United States after the war? Again, no comparison — though it was an uncomfortable shift of gear by the Americans. Greenwood recalled that the former Nazi party member had been lampooned in a Tom Lehrer song:

Don’t say that he’s hypocritical
Say rather that he’s apolitical
“Once the rockets are up, who cares where they come down?
That’s not my department,” says Wernher von Braun

Irwin concluded his lecture by mentioning four members of Gray’s Inn who played a prominent role to bringing the Nazis to justice at Nuremberg:

Hartley Shawcross QC, later Lord Shawcross, who took the lead in the opening and closing prosecution speeches.

David Maxwell Fyfe QC, later Earl of Kilmuir, who stood in for Shawcross during most of the trial.

Sir Hersch Lauterpacht QC, later Judge Lauterpacht, who was responsible for introducing the concept of crimes against humanity.

Elwyn Jones MP, later Lord Elwyn-Jones, who was junior counsel at the first trial.

All have since died, of course. So perhaps I can be forgiven for mentioning a junior prosecutor at one of the Nuremberg trials who is not a member of Gray’s Inn or even from the United Kingdom. He is Ben Ferencz, aged 100, the last living witness to the birth of international criminal justice.

Nuremberg was not victors’ justice in the pejorative sense used by Goering. But it was a small measure of justice for six million victims of Nazi Germany, among them my father’s closest relatives.

The lectures by Sir Stephen Irwin and Sir Christopher Greenwood are now available to view on the Gray’s Inn YouTube channel.

Next Tuesday at 6pm, Gray’s Inn will be holding a panel discussion called Nuremberg and After. The event is open to all but advance booking is required.

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