But once again we can only guess at the real story. But if we examine the facts they paint a slightly different picture.
The assailant was very drunk and had consumed an entire bottle of vodka. That doesn't excuse what happened but I suspect everyone reading this will have encountered drunks and know how they can do something like that completely without warning.
It was a single punch. And the victim died from striking his head on the pavement. He was 65, although to me he looked significantly older, and he was taken completely by surprise.
So the court was faced with a teenage drunk (not that rare in Merseyside) whose naturally aggressive instincts had been unchained by the effects of alcohol (again, not that rare in Merseyside) who didn't intend to kill the victim, otherwise he'd have done something other than land a single punch.
Given all that, and we know nothing about the assailant's upbringing, which might have been pretty dire (not that rare in Merseyside...) and the assailant's age (technically, he was a child in the eyes of the law) what would you have the courts do? 17-year-olds make mistakes and, in this case, it was a fatal mistake.
The sentence can be appealed, of course, but the defence can argue that the death was caused directly by the victim's collision with the pavement and not the punch.
Of course, it makes for a good story, and that's what sells papers and hence ups the revenue of the media owners. But if we can be dispassionate about the case, what were the options?