Judges at the Court of Appeal have upheld a sentence given to Lewis Gill, who was found guilty of manslaughter after punching Andrew Young, 40, in an unprovoked attack.
Mr Young later died from a head injury which he suffered when he hit the ground.
Mr Gill, 20, was sentenced to four years in jail for the offence, a decision which provoked outrage.
The incident occurred on November 6 last year outside the Tesco Metro store on Charminster Road in Bournemouth.
Gill later pleaded guilty to manslaughter and was sentenced at Salisbury Crown Court.
Attorney General Dominic Grieve argued today that the sentence was not a proper reflection of the gravity of what Gill did.
But the Appeal Court judges decided there should not be any change to the four years being served by Mr Gill.
More top news
ITV News catches up with a migrant rescued by HMS Bulwark in the Mediterranean in June who has found his way to the UK through Calais.
A low pressure system in the near Atlantic will bring a text book swirl of cloud - with blustery downpours as winds whip up tonight.
The President's announcement on climate change is yet another attempt at securing an elusive climate change legacy.