You might find it useful to look at Chapter Twenty-Three of this great novel, in which Okonkwo and the other leaders of the tribe are seized and arrested deceitfully and then forced to face European justice, which is in stark contrast to the kind of justice that was part of their culture as depicted in Chapter Ten, where the villagers are shown to bring their disagreements before a kind of spiritual entity who then pronounces their judgement. Consider what the District Commissioner says to Okonkwo and the other men arrested with him and how he paints a picture of European justice:
We have a court of law here we judge cases and administer justice just as it is done in my own country under a great queen. I have brought you here because you joined together to molest others, to burn people's houses, and their place of worship. That must not happen in the dominion of our queen, the most powerful ruler in the world. I have decided that you will pay a fine of two hundred bags of cowries.
Justice is something adminsited in a distinctly European fashion as one white man, without consulting others or any other forms of wisdom, pronounces judgement. This of course is very different from the tribal form of justice where cases are brought in front of the whole tribe and everyone agrees with the verdict.