Offences Against the Human Body
Culpable homicide is murder if the death-causing act is done: with intent to cause death; with intent to cause bodily injury the offender knows is likely to cause death; with intent to cause bodily injury that is objectively sufficient (in the ordinary course of nature) to cause death; or with knowledge that the act is so imminently dangerous it must, in all probability, cause death, done without excuse for that risk. Five exceptions downgrade what would otherwise be murder to culpable homicide not amounting to murder: grave and sudden provocation (with conditions); good-faith excessive private defence; a public servant's good-faith excess in advancing public justice; a sudden fight without premeditation or undue advantage; and a consenting adult (18+) taking on the risk of death themselves.
This precisely distinguishes murder (the most serious homicide category) from lesser forms of culpable homicide, based on the offender's specific state of mind and the presence of any of five recognised mitigating circumstances - most famously, "grave and sudden provocation", which can reduce what would otherwise be murder to a lesser offence.
This is why courts must carefully examine an offender's exact intent and any mitigating circumstances (like sudden provocation) in every homicide case - the same death-causing act can be murder, a lesser form of culpable homicide, or even no offence at all, depending on precisely how it fits this section's framework.