Lincoln Crown Court was told that James Priestley, who runs his own engineering company, believed he was about to be hit and so decided to get his punches in first and attacked Daniel Barley.
Jeremy Janes, prosecuting, said Priestley became involved in a confrontation with a couple outside a cashpoint machine on High Street, Gainsborough.
Mr Janes said: “There was a dispute about who was going to get a taxi.”
“The defendant believed the complainant was going to strike him so he gets his blows in first.”
Priestley delivered a number of blows and kicks to his victim who suffered a broken wrist and a broken tooth, the court was told.
When Priestley was later interviewed by police he admitted he had been in a fight but said he thought that the complainant was getting aggressive and that he felt he had no option but to strike the man.
Priestley ,37, of Hawthorn Grove, Gainsborough, admitted inflicting grievous bodily harm as a result of the incident on 25th December 2013.
He was given a 12 month jail sentence suspended for two years with 250 hours of unpaid work and was ordered to pay £300 compensation to his victim.
Judge John Pini QC told him: “This was an utterly disgraceful piece of conduct.”
“You should be ashamed of yourself.”
“Never ever behave in this disgraceful way again.”
Claire Holmes, defending, said Priestley, who runs his own business, had never been in trouble before.
She told the court: “He has lost his good character.”
“He is deeply ashamed of what he did.”
“He has his own business.”
“He is a dedicated family man. Over the last seven years he has built up an engineering business.”
“He has two full-time members of staff and eight sub-contractors who rely on him for work.”
“If he is sentenced to an immediate custodial sentence and that business folds then those people will lose their employment.”
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