A retired headmaster has spoken of his shock at being accused of having sex with a 14-year-old boy after being honoured by the Queen for his work with young people.

John Coatman, 75, of Leyburn Gardens, is alleged to have had a sexual relationship with a member of a Christian youth group he was involved with in the 1970s.

He was headteacher at St Andrew's Church of England High School in Warrington Road at the time of the alleged offences.

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The claims surfaced in 2014 after the breakdown of the alleged victim's marriage and problems at work, the Old Bailey trial has heard.

Giving evidence in his defence this week, Mr Coatman told jurors he had worked with around 22,000 young people in his lifetime and this was his first complaint.

He retired in 1998 after 42 years as a teacher and was awarded an MBE in 2012, the court heard.

Describing the day of his arrest in 2014, Mr Coatman said on Tuesday: "The phone was ringing and my immediate thought was one of my young people had had an accident.

"When I got there, I was arrested. It was a complete shock to me. I had no experience of this kind of thing before in my life. I had never had any sort of complaint."

He went on: "I was deeply shaken because over all my years and all the young people I have worked with I have only had tremendous successes and got on very well."

He told jurors that he had devoted himself as a teacher and "achieved what I was aiming for" when St Andrew's was listed as 16th in a national league table.

Mr Coatman, who described himself as a bachelor, denied the accusation that "rough and tumble" with his accuser had turned sexual.

He told jurors that the only physical activity the young people engaged in was British Bulldog and he had never been alone with any of them at his home.

The topic of sex did crop up during youth group meetings, but only in reference to passages in the Bible involving "Christian aspects of sexual behaviour", he added.

The alleged victim told the Old Bailey earlier this week that had been a “willing” sexual partner to Mr Coatman over 12 months in the 1970s before years later realising “the reality of what happened to me”.

He added: "The reason I said nothing was because I couldn't bring myself to admit that it had happened to me. I didn't want to accept it had happened to me.

"And believe you me I have been tormented by that guilt ever since - that if others had been victims I could have perhaps prevented it."

Mr Coatman denies buggery and two counts of gross indecency.