This is exactly what I'm struggling with. Intuitively, the idea of another person trying to injure me sounds scarier than a harness failing or tree falling. People can be a lot more unpredictable than gravity or metal fatigue. But then again, the safety of loggers and roofers depends not only on their own gear & diligence, but also on human co-workers who can be just as unpredictable. Versus violent criminals, at least the co-workers aren't actively and creatively malicious (usually).