This is a fascinating question. Paton, as a white South African himself, wrote this novel to express his fear and concern about what was happening in his country and how he saw the racial divide widening day by day. Therefore, I believe that he does his best to be impartial. There are a number of chapters away from the main action of the novel where Paton allows us to hear a wide range of different opinions about what is happening in South Africa. I believe he tries to do this as justly and accurately as possible without bias. Consider Chapter 12, where Paton is keen to present the negative effects of what is happening in South Africa on both whites and blacks:
Have no doubt it is fear in the land. For what can men do when so many have grown lawless? Who can enjoy the lovely land, who can enjoy the seventy years, and the sun that pours down on the earth, when there is fear in the heart? Who can walk quietly in the shadow of the jacarandas, when their beauty is grown to danger? Who can lie peacefully abed, while the darkness holds some secret? What lovers can lie sweetly under the stars, when menace grows with the measure of their seclusion?
The situation in South Africa is thus shown to impact all of its residence, no matter what skin colour. Note too that the novel presents both whites and blacks who are working to try and do something about the situation - we are presented with the colony in Ezenzeleni where whites work with blind blacks, and also the white worker of the reform school where Absalom was. Although Paton is keen to evoke the full danger of the situation in his country, he does not seem to place the blame in any quarter, rather making an appeal for compassion, understanding and love - as is shown by the relationship at the end of Jarvis and Kumalo.