A musician who worked on Oscar-winning comedy Wallace and Gromit: The Wrong Trousers thought he was “untouchable” before he was convicted of child sex offences – and there may be further victims, a detective has said.

Former teacher and choirmaster David Pickthall admitted at an earlier hearing at Colchester Magistrates’ Court to 29 child sex offences against 19 people and spanning more than 40 years.

He was sentenced at Chelmsford Crown Court for the crimes, committed between 1980 and 2021 in Brentwood in Essex and Upminster in east London.

The 66-year-old, who was made an MBE in the Queen’s Birthday Honours List in 2015 for his services to education and charity, was a respected figure who had worked on a number of TV and film projects.

He worked on the 1993 stop-motion animated short film Wallace and Gromit: The Wrong Trousers, with his role described as the “musical voice” of villainous penguin Feathers McGraw.

I think that perhaps because he had the title of an MBE and had worked on some TV and film projects, perhaps he thought no-one would suspect someone such as him would be capable of these crimes

Pickthall, of Ingrave Road, Brentwood, Essex, also worked on the post-apocalyptic horror film 28 Days Later and with a number of philharmonic orchestras.

Detective Constable Chelsie Stamford, the officer in the case, said the 19 victims may be the “tip of the iceberg” and she urged any further victims to contact police.

“I do think he probably thought he was untouchable because the offences spanned more than four decades and he got away with it for that amount of time,” she said.

“I think that perhaps because he had the title of an MBE and had worked on some TV and film projects, perhaps he thought no-one would suspect someone such as him would be capable of these crimes.

“But, of course, on the contrary, the crimes he committed were horrifying.”

She said that one victim made a report to police in October 2021 and this led to investigators speaking with further victims.

“It quite quickly became obvious to me that his offending was on a large scale and there were many people affected by him,” said Ms Stamford.

She said that when she interviewed Pickthall “he always remained very composed”.

“Of course he was denying the allegations right up until the point that he pleaded guilty at the first court hearing,” she said.

“I very much got the impression he thought he would continue to get away with these crimes because, of course, his crimes spanned more than four decades and he’d got away with it for that long.”

Pickthall was a “very well-respected member of the community”, she said.

“He was a teacher but he was also a musician, he did a lot of things for church and for charities, and he not only groomed his victims but he groomed their families, his friends, his colleagues,” the detective said.

“He hid behind this facade that he was a respectable individual, but ultimately because of those 19 victims who came forward and gave us their accounts, and had the courage to do that, the evidence was so strong against him that regardless of the titles he had or how well-respected he seemed to be he had no choice but to plead guilty.”

She continued: “I think this case is just the tip of the iceberg in terms of his offending and I don’t doubt there are more victims out there.

“I would strongly encourage any other victims of David Pickthall or any victims of any similar crime to report to the police because you will be listened to, you will be believed and you will be supported.

“I really want to take this opportunity to thank those victims for coming forward and speaking to us, having the courage to talk about the worst experiences of their lives because without them David Pickthall wouldn’t be held accountable for his crimes today.”

She said she hoped the 19 victims “can take some comfort in knowing that because of their courage and because they placed their trust in us by relaying their accounts to us that David Pickthall has now been held accountable”.