A man whose campaign of sexual abuse of girls was exposed when he asked one of them to be his Facebook friend has been jailed for 14 years.
The woman was 'horrified by the prospect,' of becoming a 'friend' of Gary Head and she revealed to a friend how he had abused her, Gloucester Crown Court heard.
As a result police were contacted and the other allegations then also came to light, said prosecutor Nicholas Gerasimidis.
Head, 48, formerly of Gloucester but now living in Weymouth, was found guilty by a jury after a 16 day trial of twenty charges of sex abuse over a 28 year period of his life.
Three of the charges were of rape and the jury convicted him of them by majority verdicts.
He was found not guilty of eight further charges.
In mitigation, defence barrister Christopher Gair said Head was a family man with young children and his family would be devastated by the verdicts and inevitable sentence.
Passing sentence, Judge William Hart said the verdicts of the jury showed that when he was a boy Head had indulged in 'grossly indecent behaviour' with young girls under the age of ten, ranging from digital indecent assault all the way up to rape.
"In sentencing you I have to go back to the 1970s and consider you as a youth between the ages of 11 and 15 and decide what the appropriate sentences should be," he said.
"This is significantly shorter than it would have been for an adult.
"In the intervening 20 years I would have thought you had put such behaviour behind you, but you then raped a 14-year-old on three occasions."
Head was jailed for a total of five years for all the historical offences but the more recent rapes were committed when he was an adult and so he was sentenced to nine years concurrent on each, consecutive to the five year term, making a total of 14 years.
At the start of the trial he had denied 23 sex charges against five girls ranging in age from four years old to teenagers between 1974 and 2002.
The first of his alleged victims, a Gloucester woman, told the jury she was regularly sexually abused between the ages of four and eight by Head when he was a teenager.
He had indecently assaulted her and raped her in his bedroom between 1976 and 1980, she said.
Mr Gerasimidis told the jury that Head, of Doncaster Road, Weymouth, had 'substantially and detrimentally' abused the women during their young lives.
Mr Gerasmidis said the allegations from the 1970s came to light when three complainants, now in their early 40s, came forward during police inquiries into the final girl’s allegations.
They all told how they had suffered 'pretty horrific abuse,' he said.
Witnesses would tell the jury, he said, of Head’s bullying, sadistic and unpleasant nature as a young man and how he used the girls for exploration of sexual matters.
Head had also used threats of violence to ensure the girls did not tell anyone about what had happened.
Police launched an investigation after Head had attempted to befriend his fifth victim on Facebook.
Mr Gerasmidis said witnesses would tell the jury how he raped the fifth woman after she became tired on a fishing trip with Head and her father, and went to lie down in the back of his van.
The abuse continued for a year or so and he threatened the woman, now aged 26, not to tell anyone after he had forced himself on her for sex.
Mr Gerasmidis said that when arrested by police, Head had made a complete denial of the allegations by all five women.