In an unintentional way, was it not justice that Morant and Hancock were executed?
While the execution of the Boer prisoners issue can be argued, it is pretty clear that they conspired and carried out the murder of the German Missionary, an unarmed non-combatant. And as such, they should have been executed under the laws of that era.
Witton on the other hand should not even been prosecuted.
It has been a long time since I studied it but having read all the existing material - especially Witton's book - what I remember is the evidence about Hancock and Morant shooting Hesse isn't as conclusive as many here seem to believe. The film definitely presents it that they did shoot him. However, the only strong evidence was Witton's claim that they admitted it to him after the trial had finished. Which has been challenged on occasions, not least because Witton seems to have become very bitter with the two, especially since (not unfairly) he saw it as their fault he was charged in the first place.
The whole question of whether or not they shot Hesse is potentially irrelevant considering the points others have raised about spies and their treatment. Bearing in mind the death was never investigated/resolved the film's presentation, that Hancock shot him from long range like a coward, is speculation. Equally it is known that orders were given (others did it as well) to shoot Boer prisoners found in certain circumstances. Orders that would have been substantiated had most of those involved in the chain/process not been shipped out to India or refused to testify.
As for justice in a back handed way, if you choose to believe they shot Hesse then you should really also believe he was passing information, which made him a spy, which meant that he also got what he deserved. This whole situation is not as simple as one side good, one bad, because we're talking about at the level of individuals who didn't necessarily make their own free choices about everything they did.
This was a case of Morant and his men executed to pay for the crimes of their superiors. Strictly speaking, Breaker Morant and his men were following lawful orders in shooting those men because the Boer were engaged in a guerilla war. It was the first of its kind faced by the British and they handled it badly. New tactics were required because the Boer were not wearing uniforms or identifying kit.
We now comprehend the difficulties of dealing with guerillas but at the time the Kaiser, Wilhelm II was outraged by the prisoner shootings. He was a belligerent and prickly ruler overly fond of sabre rattling. The execution of Morant and Handcock placated him and prevented Germany's entry into the first and second Boer Wars. Germany's entry could perhaps have led to an earlier beginning to World War I. Scapegoats, that's all they were. They died for Kitchener's sins.
Bored now.