Two passers-by noticed Graham Green, 59, slumped unconscious alongside another man outside the Castle Square store at around 4.45pm on October 15, 2018, Sheffield Coroner’s Court heard.
The shoppers noticed Mr Green had ‘turned blue’, and tried to resuscitate him using CPR while awaiting emergency services.
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The other man, who police have been unable to identify, regained consciousness and left before paramedics arrived.
Mr Green was pronounced dead at the scene.
His brothers, Barry and David, were present at the inquest but declined the opportunity to ask questions, and remained largely silent as the court heard the evidence.
Assistant coroner Katy Dickinson told the court that spice, a synthetic cannabinoid, along with alcohol and Red Bull had been found in Mr Green’s system.
Ms Dickinson said it was customary for her to retire for 10 minutes in order to consider her verdict, but did not consider it necessary in this case due to the clear-cut evidence placed before her.
She ruled his death as drug related.
She said: “It’s a drug-related death. It all points to that.
“Obviously, he’s had a difficult life. I would imagine that drugs were his release really.”
While it remains unclear why Mr Green was in Sheffield, he was a well known figure in Chesterfield, where he had lived on the streets for some years and had found himself in trouble with the law on multiple occasions.
In June last year, Mr Green was sentenced to 18 weeks imprisonment after being arrested for a public order offence and breaching a criminal behaviour order.
In October 2017, he was sentenced to 34 weeks in prison for assaulting a police officer and breaching a Criminal Behaviour Order twice in two days.
And just two months earlier in August 2017, he was sentenced to 118 days behind bars for threatening behaviour and performing a sex act in the town centre.
Mr Green’s recent life was also beset by tragedy, with three close family members including his son and two grandsons dying in the last five years.
His son Mark – who was also homeless – died in January 2016 after being found unconscious in the Beetwell Street area of the town.
And two of his grandsons – nine-year-old Tyler Green and 12-year-old Jordan Green – died in a house fire in the village of North Wingfield in Derbyshire in 2013.