A worker in a care home for severely disabled adults has been jailed for 12 years for sexual assault after one of his victims gave evidence by blinking her eyes.

James Watts, 57, thought that he had found the perfect victims: four women so disabled that they would never be able to tell anyone what had happened. But thanks to the determination of his victims to testify, he was convicted after a three-week trial at Exeter Crown Court that the judge described as the most difficult he had heard.

Watts, a minibus driver, was convicted of six of 13 charges after the jury heard from his victims, three of whom suffer from cerebral palsy and a fourth who has brain injuries. The charges of which he was cleared included three of rape.

The jury watched video of a police interview in which one of the women used a pointer on a computer screen to tell police what had happened to her. She moved the pointer with a joystick on her wheelchair and used it to highlight a picture of the defendant when asked if there was anyone she wanted to talk about. The woman then used symbols of body parts to describe what Watts had done to her.

She said that the assaults had taken place on several occasions on day trips away from the home. A policewoman asked: “Are there any other pictures of how you felt when he did that to you?” The woman selected a symbol and the computer said the words, “I cried”.

Judge Graham Cottle told Watts that his offences would be viewed with “utter revulsion”. He said: “You descended to a level of depravity which is quite beyond comprehension. Each of the service users involved was chronically disabled. In addition to their disability each was suffering from a severe mental disorder.

“Their means to communicate at any level varied,” he added. “One was never able to communicate at any level at all, another could communicate via icons on a computer, the third can communicate by movements of her eyes and the fourth, while able to communicate at the time of the police investigation, by the time of the trial, had lost any ability to communicate at any level at all.”

One of the victims gave her evidence by video link, blinking her eyes to answer yes or no to questions from lawyers.

Paul Dunkels, QC, for the prosecution, had told the jury that Watts’s victims were unable to resist or give their consent because of their disabilities.

The abuse came to light when a Japanese woman who was a volunteer at the home saw Watts touching one of the victim’s breasts with his hand as he fed her. The woman, who gave her evidence via video link from Japan, said that she reported what she had seen only when she saw him do it again several months later.

Watts denied all the allegations. The jury took 16 hours to reach majority verdicts.

The Crown Prosecution Service’s Crown Advocate for Devon and Cornwall, Ann Hampshire, said: “Crimes involving a breach of trust like this are extremely serious. People working in the care sector, whether they are care workers, managers, drivers, catering staff or in any other role, have a duty of care to the people with whom they work.

“These offences are aggravated by the vulnerability of the victims and the courts are likely to impose harsher penalties on people who are convicted of them.”

Detective Inspector Andy Berry, whose team led the inquiry, said: “It sends out a message to offenders that they cannot abuse the most vulnerable members of society.

“The sensitivity and complexities involved were completely unlike anything I had dealt with before.”

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