"The difference between manslaughter and murder is premeditation!"
Not necessarily. A court would have to prove that the assailant had an intent to kill or causing grievously bodily harm with the intent to cause serious injury resulting in death. The state of mind needs to be proven for premeditation.
However, manslaughter can still be murder without premeditation. The degree of force or the types of actions would needed to be proven, that the assailant knew the probability that the actions could result in death.
In this case, it's been we'll publicised that one punch can, and has, caused several deaths recently in Australia. The assailant launched 3 punches to the victim. But a court would be battling to prove that he knew the possible outcome of his actions. His lawyer could argue that his drug/alcohol induced mind couldn't have rationalised his actions...blah blah blah, you know lawyers.
The following is NSW legislation but I found it very interesting.
"Thirdly, it may be argued that the murder/manslaughter distinction is artificial because murder and manslaughter are in fact regarded as degrees of one offence, rather than as two separate offences. This is evident from the fact that an accused may be convicted of manslaughter where he or she was indicted for murder, despite the common law rule that prevents conviction for one felony on the charge of another.26 If murder and manslaughter are regarded as parts of a whole, it may be argued that it is artificial to retain the barriers between them, and that instead the law should implement a unified scheme for homicide offences."
