Tony Wilkinson, who lived in shared accommodation in Barnsley, had a genetic disorder known as Fragile X syndrome, causing intellectual disability and behavioural and learning challenges.
Although the “loving and happy” 57-year-old was supposed to only be given mashed food and thickened drinks because of the risk of his choking, Sheffield Coroners Court heard a week before the tragedy he went on a trip to Cleethorpes with others, accompanied by a support worker, and was given fish, chips and mushy peas.
On April 5 2018, he was taken for a meal to a pub at Manchester Airport by a non-regular support worker. Mr Wilkinson began choking and collapsed inside the pub toilets.
Paramedics took him to Wythenshaw Hospital A&E where he was taken to theatre to have pieces of burger removed from his lung. He died as a result of a foreign body airway obstruction, having suffered a cardiac arrest.
Since 2014 Mr Wilkinson had been provided with care by private company, Stars Social Support Limited, which was commissioned by Barnsley Council. Initially he went to a day centre and staff visited him at his home.
But with his condition worsening and following a choking incident in February 2018, staff were required to provide 24-hour care and supervision.
A speech and language therapy assessment established Mr Wilkinson was unable to manage his own eating, drinking and swallowing needs, and warned he faced the very real risk of choking, and death, should he not be provided with mashable food and thickened drinks.
However the inquest heard staff were confused as to what foods Mr Wilkinson could eat and he had access to other residents’ food at his shared home.
Logs kept by staff showed he was provided with food that was outside of the guidance following his assessment.
Solicitor Simon Wilson, of Hudgell Solicitors, who represents his sisters, June Mcdonald and Linda Swallow, said the “inconsistent and inappropriate” care ultimately cost Mr Wilkinson his life.
The jury found Stars had failed to provide safe care and returned a verdict of unlawful killing on Tuesday.
Coroner Abigail Combes had advised them they could conclude "unlawful killing" if they considered the case to meet the test for either corporate manslaughter or gross negligence manslaughter.
Stars has two weeks to provide written evidence to the coroner of the measures being taken to address the concerns raised.
His sisters said it had been “really hard” to listen to the evidence and hear “so many people and organisations try and pass the buck”.
They said: “This was our brother’s life and yet nobody wanted to be accountable...
“Instead of the wonderful memories we had of him, how loving and happy he was, we are now left with the images of him lying in mortuary.
“The choking incident in February 2018, when abdominal thrusts had to be performed on Tony dislodge food, and he was blue lighted to hospital and the subsequent speech and language assessment, should have highlighted and prompted management to reassess the procedures in place to ensure his care plans were read, understood, and followed by all as a matter of priority.
“That clearly didn’t happen as he was then taken out twice, firstly given fish, chips and mushy peas, and then a burger which killed him.
"Had this company acted in the way it should have, our brother would still be with us today.
Stars was rated as "inadequate" following a Care Quality Commission inspection last August.
Stars declined to comment when approached on Thursday.