Crimes Without Perpetrators?

Nepal and Kenya exhibit certain similar qualities but none of those is as stark as having crimes without perpetrators. For instance we have never known who committed crimes during the post election violence of 2007/8. I bet we might never hold anybody accountable. Go and look at what is happening 40 years on after Nepal's internal conflicts.

Can we simply say such crimes never occurred after all or do we still keep holding unto hope that some day some miracle will occur and we shall know who was responsible for what and why? Leave alone punishing anybody, it could be a high up dream.