Chapter 20 discusses some of the clashes in values that take place between the British Courts and the Nigerians.  The narrator says that "apart from the church, the white men had also brought a government.  They had built a court where the Distirct Commisioner judged cases in ignorance."  The British Courts were seen as ignorant because they had no idea why the Nigerians did what they did - the British didn't understand Nigerian customs, traditions, or laws yet they were punishing men and trying them in court by British standards.  Some of the prisoners were being held and punished for throwing away twins and some for "molesting the Christians".  While in prison, the Nigerians were forced to work, and the narrator notes that some of the men were of high rank in the tribe, and being forced to work was humiliating.  

Chapter 20 also discusses how the British Courts decides arguments over land even though they do not know the Nigerian customs about land.  The British simply state that the Nigerian customs are bad, and the clan begins to believe it.  Obierika states, "the white man is very clever.  He came quietly and peaceably with his religion...Now he has won our brothers, and our clan can no longer act as one.  He has put a knife on the things that held us together and we have fallen apart."  (Hence the title of the novel).