Cain Byrne, 20, inhaled nitrous oxide from a balloon
Neil Shaw Assistant Editor
13:02, 21 Jul 2025
Cain Byrne hit Graham Slinn, 81, on a road near Todwick, South Yorkshire (South Yorkshire Police/PA)
A driver who inhaled nitrous oxide from a balloon before and after killing an elderly cyclist at a pedestrian crossing has been detained for more than 11 years. Cain Byrne, 20, ignored a red light and was well over the 50mph limit when he hit Graham Slinn, 81, throwing him at least 15ft in the air.
Sheffield Crown Court heard Byrne, who has never held a driving licence, made no attempt to stop at the crossing and could have been travelling at up to 80mph, according to a witness. On Monday he was sentenced to 11 years and six months’ detention in a young offenders institution, with an extended licence period of five years. He was banned from driving for 17 years and eight months.
Father-of-two Byrne, of Chesterfield, Derbyshire, admitted causing death by dangerous driving and a number of other offences at a previous hearing. An earlier hearing was told Mr Slinn had dismounted and was walking across the A57 near Todwick, South Yorkshire, when he was hit by a Volkswagen Golf driven by Byrne.
The defendant sped off with two passengers after the collision on April 4, with dashcam footage showing his tyres smoking as he appeared to be trying to control the vehicle. A montage of footage shown in court showed him inhaling nitrous oxide gas from a yellow balloon a number of times as he was driving, both before and after the collision with Mr Slinn.
One of these was just moments after he hit the former builder, who helped care for adults with learning disabilities after he retired and was weeks away from celebrating his 60th wedding anniversary with his wife Jaqueline. Sentencing Byrne, Judge Jeremy Richardson KC said inhaling nitrous oxide was “an exceptionally dangerous act while driving”.
He said Mr Slinn was “crossing the road entirely lawfully, in accordance with the green light for him”, and “died of injuries inflicted by your truly appalling driving”.
Graham Slinn was killed by a driver who failed to stop at a red light (Family handout/South Yorkshire Police/PA)
The judge said Byrne “endured a dreadful upbringing” and “had known very few boundaries” in his life. He told the defendant: “You are a dangerous offender and the public must be protected from your evident dangerous and ingrained criminal behaviour.”
Byrne was due to be sentenced last month but, after hearing about his “astonishing and appalling” driving record, Judge Richardson said he wanted a report prepared by probation officers. The court heard Byrne had a range of convictions for 27 offences, including dangerous driving, despite having no driving licence.
Rebecca Stephens, defending, told the court her client drove off because he believed he had only hit another vehicle with his wing mirror. In a statement read to the judge at an earlier hearing, Mrs Slinn said she and her husband met through a love of cycling and he rode his bike several times a week.
He was also a keen singer who would perform in pubs and clubs in Sheffield. Mrs Slinn said: “Sixty years of marriage, almost, wiped out by the defendant.”
After the sentencing, Mr Slinn’s daughter Nicola, and son Victor, described their father as “kind to his core” and said his death was “100% avoidable”. “On the afternoon of April 4, our dad set out on his bike — something he had loved since his youth, when he used to race.
“Cycling was a lifelong passion and a shared family activity. He always took safety incredibly seriously and had planned his route to stick to quiet lanes and cycle paths. Despite taking every possible precaution to stay safe — dismounting at the end of the cycle path, waiting for the lights to change to green for pedestrians, and wheeling his bike across the pedestrian crossing — on the day he died, he was hit at speed by a car driven by someone who just kept going, as if our dad wasn’t even there, as if he was nothing.
“But he was there. He was everything to us. He was our dad, our mum’s husband of 60 years, a granddad to two teenage girls, and a friend to so many.”
In a statement released through Thompsons Solicitors, the family said Mr Slinn’s death had left a profound silence at the heart of their home. The family added: “To lose any loved one is a shock. But to lose someone so vibrant, so active, and to know their death was 100% avoidable is doubly cruel.”
