The family of a man who died in custody after stealing a gingerbread man from a looted bakery during the London riots have launched a High Court claim over his death.
James Best, 37, of Croydon, London, was in Wandsworth Prison in September 2011 awaiting sentence when he suffered a heart attack.
His foster mother and brother, Dolly and Owen Daniel, claim that St Georges Healthcare NHS Trust and the London Ambulance Service breached their duties under Article 2 of the European Convention on Human Rights, which protects the right to life.
They also allege a breach of Article 3 which says that nobody should be subject to "inhuman or degrading treatment".
Counsel Kirsten Sjovoll told Mrs Justice Lang in London that there was an unreasonable delay by the nurse on call in requesting an ambulance when she arrived at Mr Best's cell - despite it being apparent that there was a real and immediate risk to his life.
It should have been summoned within one to two minutes - while the defence view was that five or so minutes was reasonable for her to carry out assessment.
There was also an alleged failure - both in the system and individually - to dispatch an ambulance without unnecessary or unreasonable delay once the 999 call was received.
Ms Sjovoll said: "We are talking about a cardiac arrest. Seconds count and minutes matter.
"We are talking about medically-trained professionals who knew or ought to have known that this was a life-threatening situation and should have acted quicker to do something about it - that is call 999."
She added that it would have been a "very distressing" way for Mr Best, who was vulnerable due to his mental and physical health problems, to die.
It was not disputed that it could not be shown on the balance of probabilities that Mr Best would have survived but for the alleged failings.
It was not a negligence action - and all that needed to be shown was that Mr Best lost a "real" or "substantial" chance of a different outcome, said counsel.
Mrs Daniel, who fostered Mr Best when he was 15, wept as she gave evidence.
She said that the principle aim of the claim was not damages but an apology for the "shortcomings" identified at his inquest in March 2013.
"We think that James deserved the respect and dignity after his death that he certainly was not accorded in the manner of his dying."
Mrs Daniel, who worked as a complaints manager with the NHS for a decade, added: "I did a lot of work with bereaved families and I tried to treat them a lot better than we've been treated."
The trial, which is only concerned with the contested issue of liability, is expected to last five days with a decision reserved to a later date.