I'd love here how it is that the prosecutor on a case like this, doesn't know that the lead investigator is facing seven charges of attempted murder.The answer I have is basically a special case of my Grand Theory of Why South Africa is Such a Fucking Basketcase. In brief: South Africa has a horrible case of corruption. It has this problem because it is for the moment a one-party state with all the associated problems that brings in a brutalized country: a crap education system, rampant cronyist promotion of incompetents, graft, etc. It is a one-party state because the ANC (through the personage of Nelson Mandela) is credited with ending Apartheid, and the largest competitor party is fatally associated with whites. Without real political competition, there is no consequence for corruption.
This is quite similar to what happened all across Africa after the end of colonialism—countries started democratic and toppled into authoritarianism due to weak institutions, lasting damage from colonialism, and a failure of political culture.
Finally, on a more subjective note, the lasting damage that Apartheid did to the South African national psyche is truly immense, and compounds all these problems. Visit there, then Botswana, for a taste of this.