It was the programme that shocked the nation.
BBC One's Panorama showed patients at a residential care home near Bristol, being slapped and restrained under chairs, having their hair pulled and being held down as medication was forced into their mouths.
The victims, who had severe learning disabilities, were visibly upset and were shown screaming and shaking.
One victim was showered while fully clothed and had mouthwash poured into her eyes.
Undercover recordings showed one senior care worker at Winterbourne View asking a patient whether they wanted him to get a "cheese grater and grate your face off?".
The abuse was so bad that one patient, who had tried to jump out of a second floor window, was then mocked by staff members.
Andrew McDonnell, who works with adults with mental disabilities, labelled some of the examples seen on film as "torture".
Dr Peter Carter, head of the Royal College of Nursing, said: "The sickening abuse revealed in this programme is more shocking than anything we could have imagined."
'How could this happen?'
One of the victims, Simon Tovey, was seen being repeatedly assaulted and mentally abused by the care workers.
His mother Ann told the programme: "They're just having their amusement and their fun. How can that ever be allowed to happen?"
That is a question the authorities were not able to answer.
The programme told a story that former Winterbourne View nurse Terry Bryan never could.
He had contacted the private hospital's bosses and the regulator, Care Quality Commission (CQC), about the abuse - however his concerns were ignored.
"I know the way it works, other people don't have that knowledge. So if I can't get anything out of the people at the CQC, then I worry that others won't get anywhere near them," he said.
Eleven care workers were sentenced after admitting 38 charges of neglect and abuse. Six were jailed for between two years and six months, while the others received suspended sentences.
Castlebeck, the care home's owners, apologised and its new chief executive said he was "ashamed" to be associated with a company where abuse had happened.
The CQC said it was a "misjudgement" that Mr Bryan's concerns had not been investigated.
The home has now closed and the building's new owners have stripped it bare. There is not one reminder of the abuse that happened.
Although horrific, the programme encouraged others to speak out about concerns of private hospitals.
The CQC says more than 4,300 whistleblowers have come forward in the past 20 months to complain about the treatment of elderly and disabled people in care.
It added this was partly down to the impact of the programme.
'Out of sight, out of mind'
Beverley Dawkins, the national manager for profound and multiple learning disabilities for Mencap, said the charity had noticed a surge in inquiries from families concerned about this type of abuse.
"I don't think there are more and more awful things happening, but awareness has been heightened.
"People know who to contact and to do it as soon as possible when they become concerned."
She said families who may have reported concerns before which were not looked at now know that now is the time to raise them again.
"The sobering thing about Winterbourne is that it took a secret camera to find out what really was going on.
"We know spotting abuse can be pretty challenging and even with increased unannounced inspections, some of this stuff goes on behind closed doors."
Vivien Cooper from the Challenging Behaviour Foundation said: "The programme shone a light on a particular type of service and it raised the profile of individuals who had been hidden, who were out of sight and out of mind."
She added: "When the programme came out people were very shocked by the abuse they saw. It was shocking for the general public but for people with families of learning disabilities it was worse, as they would have thought 'that could be my son or my daughter'."
The two charities are now campaigning for people with learning disabilities to be supported to live in their local communities close to their families.
An independent report said fundamental changes were needed in how care of vulnerable adults was commissioned and monitored.
An interim report by the Department of Health into Winterbourne View said commissioning across health and care services should aim to reduce the number of people in treatment and assessment centres.
The full report is due to be published.
In Parliament, Tom Clarke, Labour MP for Coatbridge Chryston & Bellshill, said the current care model, and the regulation of it, led to these abuses, and urged the government to close large assessment and treatment centres like Winterbourne View and instead offer support for individuals to live in their communities.
"We cannot erase the evidence of abuse, where and when it happened," he said.
"We cannot undo the pain, the suffering and humiliating experience endured by people with learning disabilities, and we most certainly cannot leave it to the monolithic bureaucratic machine to ensure that such abuses never occur again."