A thug who gatecrashed a 40th birthday celebration and hit two off-duty police officers with a beer bottle - leaving one partially blinded - has been jailed for five-and-a-half years.

Jack Botton hit partygoers John Fleming and Stuart Dark to their heads on a fire escape staircase outside The Farmhouse in West Malling.

Botton, 22, was joined in what a judge described as “late-night drunken aggression and violence” by Tommy Dunn.

The 24-year-old repeatedly punched both men despite their bleeding head wounds.

The pair were among a group of about a dozen men who headed from the pub bar to the private function room upstairs at about 11.30pm on May 10, 2013.

They were said to have an aggressive demeanour and ignored polite requests to not go into the party, being enjoyed by about 70 guests with ages ranging in their 30s to 60s, and then to leave.

But Maidstone Crown Court heard violence erupted after Mr Fleming and Mr Dark had managed to edge them out of the room and back onto the fire escape.

Jailing Botton, and Dunn for 13 months, Judge Julian Smith said the two officers had shown them no aggression.

Having viewed CCTV of the incident he added: “These mature men, experienced in situations of public disorder and high stress, remained calm and controlled as you in due course became more violent and aggressive.”

Botton, who lives on a caravan site in Windmill Lane, West Malling, admitted two offences of wounding with intent. He will serve half his sentence less 285 days spent on qualifying tagged curfew.

Dunn, of Bondfield Road, East Malling, admitted two charges of assault causing actual bodily harm. But he is expected to be released within weeks, having spent four months on remand and 234 days on qualifying tagged curfew.

Prosecutor Edmund Fowler told the court Mr Fleming and Mr Dark had managed to edge the men back out onto the fire escape when trouble flared 30ft above the ground.

Botton struck a “forceful and deliberate” to Mr Dark’s forehead with the bottle, before hitting Mr Fleming.

“He went to the ground almost immediately with the force of the blow and his face bleeding profusely,” said Mr Fowler.

“Dunn then started punching both men to their heads. Mr Dark was trying to strike back to defend himself while trying to help Mr Fleming.

"I'm pleased that the wholly unnecessary violent actions of these two men have now been punished..." - Det Con Paul Newton

Several people called police but the court heard it was half an hour before they arrived.

Although the bottle did not smash, Mr Fleming suffered a 4cm cut over his left eye and another to his lower eyelid.

Mr Dark had a 2cm cut to his cheekbone, a 1cm cut to his forehead and another over his eye.

Botton and Dunn were arrested five days later. Botton claimed he had stayed in the bar downstairs and, when shown CCTV images, that he could not recall any of the violence.

Roy Brown, defending, told the court Botton now wanted to apologise for his “loss of control”.

Dunn, who was described by his barrister Philip Sinclair as “a sizeable young man but not quick with his fists”, made no comment.

Passing sentence, Judge Smith said there was no evidence to suggest that one of their friends had been “attacked, assaulted or ill-treated” by the partygoers.

After sentencing, Detective Constable Paul Newton said: "Botton and Dunn were both intent on causing trouble that evening.

"The victims had identified themselves as police officers and performed their responsibilities irrespective that they were off duty.

"The offenders were then responsible for an entirely unprovoked assault, which has caused long term damage to one of their victim’s eyes.

"This has forced an experienced police officer to become non-operational, due to the scale of his injury, as it is unlikely he will ever regain full vision.

"It has taken a long time to get justice in the investigation, and I would like to thank the numerous witnesses involved in this case. I’m pleased that the wholly unnecessary violent actions of these two men have now been punished."

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