Our souls can choose the path of our lives before we incarnate. But when that path forks, we as incarnated beings have to choose whether to learn the lesson we came here for, or not. We cannot learn another's lesson for them, much as we ache to relieve the pain and suffering in their lives. My cousin was also convicted of murder, and I watched his family struggle for decades to make sense of it. That struggle killed his parents much earlier than they should have died, and fractured his siblings with resentments about who did what. The worst part being that no one ever knew if he actually did it, because there were no witnesses, and he had no memory of that day.