In many common law jurisdictions (not including my part of Australia any more, but still in many other parts of the Commonwealth), murder is a crime defined by

In many common law jurisdictions (not including my part of Australia any more, but still in many other parts of the Commonwealth), murder is a crime defined by the common law - these days, statutes set what the maximum sentence of a murder conviction can be, but the definition of the crime itself is a common law definition.