Fact: A causes an injury to Z, which results in his death. It was never intended by A to cause his death nor in normal conditions could it have caused Z's death. What offence A has committed? Issue: What offence, if any, has been committed?

A caused an injury that resulted in death, but the death was neither intended nor would it normally occur from such injury in ordinary circumstances. This rules out both murder (which requires intention) and culpable homicide (which requires knowledge that the act is likely to cause death). Therefore, A is only liable for causing simple hurt under Section 323 IPC.