This is the moment John-Paul Smith smashes his head down on a woman's face in a nasty attack in Medway.

It happened in May this year as Smith was walking home with friend Kirsty Bryant and the footage has just emerged.

The original footage, shown during a four-week murder trial at Maidstone Crown Court, caused the jury to gasp.

Yet Smith – who was a prosecution witness in that case - was never charged with the assault on Ms Bryant... a decision questioned by a senior lawyer.

Despite having a previous conviction for violent disorder, the 26-year-old escaped with a caution.

The incident – caught by CCTV – happened as the couple were walking along a street in Gillingham late at night.

The two, who appear to have been drinking, stop near a wall when Smith begins to pester Ms Bryant.

He then shoves her before headbutting her - causing her to fall to the ground.

She was covered in blood and suffered severe bruising to her nose and face – but did not want to take case further.

However, Crown Prosecution Service guidelines say he should have been charged with an assault causing actual bodily harm – especially as it was captured on CCTV.

On conviction, he could have faced a jail sentence of up to nine months. Instead he was given just a police caution - which is only given if he admitted the assault.

One senior lawyer, not connected with the trial, said: "When you watch the video it is utterly ghastly.

"No wonder the jury gasped. Under CPS guidelines he should have been charged with a Section 47 assault... but to be let off with a caution is clearly a case of under-charging."

The attack happened a couple of months after Smiths' friend David Young was stabbed to death.

Smith was also stabbed in the attack and both he and Ms Bryant appeared as witnesses for the prosecution.

Thomas Hodge, 17, of Beatty Avenue, Gillingham, was cleared of murder but convicted of manslaughter and given a seven-year sentence.

The trial at Maidstone Crown Court heard how Mr Young, his partner Kirsty Bryant, his brother Aaron, Mr Smith and another couple could not get a taxi in the early hours of January 1 after a night out in Rochester.

They started the long walk home to Gillingham and trouble flared when they met up with the two teenagers and their girlfriends in Windmill Road.

Ms Bryant became involved in a fight with the teenagers' girlfriends and the clash spiralled out of control and ended with the victim, of Beatty Avenue, Gillingham, being stabbed in the left thigh.

The father of two was taken to nearby Medway Maritime Hospital, but the blade had severed an artery and he died four days later on January 5.

Ms Bryant has since launched a campaign calling for a crackdown on knife crime including tougher sentences.

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