The church warden is accused of sexually abusing the boy on various occasions – including while camping and on a sailing trip.
The jury heard how the former teacher would give the teenager money, and buy him cigarettes and alcohol, and sometimes they would smoke cannabis together.
Mr Carter said: “Such sexual activity was not confined to the boat. The final occasion was one where he had tied his trousers to prevent them being removed and woke to find Barton-Wood trying to pull them down.”
In 2001, the victim contacted Mr Barton-Wood, saying he wanted to meet to find out why he had done what he did, the court was told.
In a statement, Mr Barton-Wood, of Wymondham, Norfolk, claimed he was being blackmailed.
Mr Carter said: “He felt the email was in some way threatening. [The victim] said there were things he could say about him and Richard Barton-Wood felt he was