While I don't think that we can make a definitive statement that justice in "Africa" was nonexistent, the very idea of considering "Africa" as a single homogeneous environment or domain of policy is incredibly reductive at best.

Even the specific examples given of "restorative justice" are pretty much identical but less formal than the Roman Law counterparts.

> For instance, in ancient Zimbabwe, if you killed someone, you would pay 109 goats. If you had no goats, you would offer one of your children to the victim’s family. If you did not have a child, an adult from your family would go live with the dead person’s family.

I find this nearly impossible to believe that all of the hundreds of clans spanning tens of ethnicities that resided in what is present day Zimbabwe had "109 goats" encoded in their traditions, much less that oral traditions had sufficient stability over generations that this is even a sensical statement. If we accept the dubious idea that this was codified in a uniform way then the question is how does this differ from other traditions? Restitution for murder to avoid blood feuds was an essential part of both Roman and Germanic law traditions, as is subjugation and slavery (in the non-chattel sense used in the book).