A man with learning difficulties who was tortured and murdered by a gang was failed by "every part of the service system" in Cornwall, a review has said.
Mr Hoskin was under the care of Cornwall social services
The serious case review by the Cornwall Adult Protection Committee looked at circumstances leading up to the brutal death of Steven Hoskin in July 2006.
The review found more than 40 warnings and chances for intervention were missed by the agencies involved.
It makes 17 recommendations for improving services in Cornwall.
They include improving community safety with multi-agency conferences and information sharing, raising the understanding within local communities about vulnerable adults and restoring public confidence.
Steven Hoskin, 38, of St Austell, was tortured and then taken to a viaduct and forced to hang from railings.
Sarah Bullock, who stamped on his hands causing him to fall 100ft to his death, was detained for 10 years for murder.
Her boyfriend and gang leader Darren Stewart, 30, was jailed for at least 25 years for murder.
Martin Pollard, 21, was given eight years for manslaughter.
The case against two 17-year-old youths, who cannot be named for legal reasons, was adjourned for pre-sentence reports.
The review revealed that police were aware Stewart was dealing drugs from Mr Hoskin's home in November 2005.
Both Stewart and Mr Hoskin were known to care services and the police.
Bullock, who was 15 when she met Stewart, was known to the Youth Offending Team and children's social care services after leaving school.
The report revealed that Mr Hoskin had cancelled his own care in August 2005, but was not risk assessed.
Two of the gang were known to police and care services
The report said he made 12 calls to the police for various matters, including threats to him, between the time he cancelled his care to a month before he died.
"The fact that individuals in all agencies knew that Steven was a vulnerable adult did not prevent his torture and murder," the report said.
Dr Margaret Flynn, chairwoman of the review, said there were warnings that should have triggered an adult care alert.
She said: "At every stage following Steven's departure from his family home all serious case review contributors could have been potential rescuers, but every part of the service system had significant failures in this role."
Sheila Healy, chief executive of Cornwall County Council, said: "This was a terrible case of murder and our sympathies go out to his parents and family.
"We have a commitment to ensure that Steven's lasting legacy is action to minimise the possibility of this ever happening again."
Ch Supt Rob Cooper, police commander for Cornwall, said the force had since appointed two adult protection officers in Cornwall and introduced daily review processes to highlight potential areas of concern.
A senior officer was appointed to develop all strands of adult public protection and a central referral unit to ensure good working relationships with partner agencies.
Devon and Cornwall Police said: "The serious case review has identified a number of areas for the police where improvements in our working processes will assist in the early identification of adults in need of care or support.
"Such identification will assist in preventing anything as shocking as this ever happening again."