'I hate what they've done, it is the worst thing'
Swift's friend Jack Sanderson-Hunt, also 18, of Dundry View, Knowle Park, earlier pleaded guilty to manslaughter and both will be sentenced at a future date.
Swift will receive a mandatory life sentence, with a minimum term of imprisonment to be decided by a judge, and Sanderson-Hunt could also face a life sentence, although his punishment for manslaughter is likely to be more lenient.
But Joe's father said the length of sentence won't make any difference to him.
Mr Williams told the Post: "They could be hung every day for the next 500 years. The verdict and the sentences won't make any difference.
"They killed Joe and they killed my family as individuals.
"I hate what they've done, it is the worst thing. I would rather die 10,000 times than what happened."
During the trial the jury heard how Joe was felled by a single punch from Sanderson-Hunt as he tried to stop a row in Queen Charlotte Street in the city centre on June 21 last year.
As he lay unconscious with a fractured skull, Swift kicked his head "like a football" to the right temple, causing a second fracture.
Although attempts were made at Frenchay Hospital to save his life, Joe, a popular St Brendan's Sixth Form College student from Whitchurch, lapsed into a coma and died as a result of his head injuries two weeks later.
Mr Williams, 44, a former printer from Wells Road, Whitchurch, had been working towards becoming a bereavement counsellor before his son was murdered – but was dropped from the course following the tragedy.
He and his family attended Swift's murder trial every day.
Mr Williams said: "When the verdict was returned, everybody shouted 'yeah!' from the upper public gallery and it seemed it was like winning and losing. There is nothing to say we won – we've lost Joe. The simple fact is Joe's dead – no matter what happened in court, he remains dead."
Mr Williams told how he spent "all the time" with Joe at football training, and he was proud of the fit and healthy lad who went on to play for Yate Town and Bishop Sutton under-18 squads.
He feels that neither Swift nor Sanderson-Hunt have shown any remorse for the precious life they ended.
He said: "Those two killed Joe 43 weeks ago yesterday. They were released, and walking around free and I know they have been walking around thinking they would get away with it.
"Swift was out as if nothing had happened. He's either in complete denial or he's completely cold."
Mr Williams said more than 80 witnesses came forward after the murder, and he described their help to the police investigation as "brilliant".
He said Joe was extra special for him and his wife, Gabrielle, 41, because they lost their first son Ben from a heart defect when he was just five days' old.
Mr Williams said the pain of Joe's death was heightened by the fact there were three autopsies – so they couldn't even bury him with dignity.
He said: "Ben died, but Joe was killed. Joe was innocent, he did something decent and he was murdered."
Michael Fitton QC, prosecuting, told the court that on Saturday, June 21 last year, Joe went out with his friends Jack Pullin and Pedram Motallebzadeh.
He said that Mr Pullin had been going out with a girl called Sophie White, and on that night she was out with her friend Vicky Godfrey.
Mr Fitton said that when Miss White and Miss Godfrey were in the Chicago's venue in Canons Road, they bumped into Sanderson-Hunt and Swift, who Miss Godfrey knew, and the four chatted before going to QC Bar in Queen Charlotte Street.
Mr Fitton said: "When Jack Pullin arrived and saw Sophie White there, the couple argued.
"After the argument Jack, Pedram and Joe left QC Bar to go elsewhere. Jack and Sophie had argued and they were exchanging rude telephone calls and text messages.
"After a while Jack, Pedram and Joe came back to QC Bar and Jack went up to Sophie and they argued."
The jury heard Miss White was "drunk, angry and aggressive" towards Jack Pullin, swinging her arms and trying to punch him.
Mr Fitton said: "Joe Dymond-Williams took it upon himself to step between them, to intervene. Sophie was being aggressive and he took hold of Sophie to restrain her. It's at this stage that Jack Sanderson-Hunt and Thomas Swift became involved."
The jury heard that witness accounts varied as to what happened after that.
The Crown said Sanderson-Hunt punched Joe hard in the face and he fell straight back and knocked the back of his skull, causing a 10cm-long fracture. As he lay unconscious, face-up, Swift admitted kicking him as hard as he could to the right side of his head, causing a second 3.5cm-long fracture.
Witness Nicola Grant told police she saw one man punch Joe before another kicked his head "like someone would kick a football".
The court heard that after the assault, bystanders tried to prevent the attackers from leaving the scene – but when Thomas was grabbed, Sanderson-Hunt helped him escape and they both fled.
Sanderson-Hunt was chased to Pero's Bridge on the waterfront, rang his father and got into his Mercedes car. Swift was chased to Princess Street, Mr Fitton said, but when his pursuers grabbed him, Sanderson-Hunt arrived with his father and, once again, helped Swift to get away.
Police then arrived and arrested Sanderson-Hunt, and he then helped them contact Swift, who was arrested from College Green.
At first Swift gave a false name and told police he had not assaulted anyone, but went on to give his proper name and said he kicked Joe to see if he was conscious.
As she left court, Swift's tearful mother told assembled police officers: "The real offender got away with it... Jack Sanderson-Hunt got out the back door."
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