The former Ampleforth pupil choked back tears in the witness box this week and told Turner directly that he had turned him into a deeply-troubled insomniac who suffered flashbacks to his childhood trauma.
He said: “What you did to me has pervaded every aspect of my life in the most devastating of ways. For 35 years I have not slept through the night – not once since you started abusing me.
“What you did to me physically, repeatedly and systematically, destroyed my mental wellbeing and … destroyed my sleep. You saw me as an object of your sexual and pathological gratification."
Turner was this week jailed for 20 years and 10 months after he admitted sexually abusing three boys in the 1980s and 90s.
The depraved clergyman showered the victims with attention and gave them treats before subjecting them to “the most vile” abuse.
Turner plied one of his victims with altar wine and at least two of the boys were abused in a church vestry, York Crown Court heard.
Turner, now 80, a former monk and teacher at Ampleforth College - the prestigious Catholic boarding school in the North Yorkshire Moors - was told he must serve at least half his sentence behind bars after admitting 14 counts of sexual abuse including 11 counts of sexual assault, two counts of buggery and gross indecency with a child under 13.
The pensioner, who had protested his innocence until the last minute, admitted the offences just before his trial was due to get underway on Tuesday. Three other charges were left on file.
At the sentence hearing on Wednesday, prosecutor Tom Storey said the “clearly depraved” former monk repeatedly sexually assaulted an Ampleforth pupil at various locations including a hostel in the grounds of the school.
He groomed and sexually exploited the boys between 1984 and 1990 but is said to have abused others, possibly up to 2002.
Turner was turfed out of Ampleforth College in 1987 after confessing to having sexual contact with the named pupil, but police were not called in and Turner - known as Father Gregory Carroll at the time - was sent to a parish in Workington, Cumbria, where he soon targeted two boys at the church where he worked.
Turner, who was in his 40s at the time, was recalled to Ampleforth in 2002 and confined to the abbey to live a monastic life, but it wasn’t until 2005 when his wider sexual offending came to light following the publication of the Nolan Report into child sexual abuse among the nation’s priesthood.
He was sentenced to four years in prison in 2005 - later reduced to three years on appeal - for abusing 10 other boys who were never named.
It was while serving his sentence for those crimes that one of the boys in the Workington parish came forward with allegations about Turner, but they were not followed up by the Crown Prosecution Service because they were not deemed to be in the public interest due to the cleric already serving a jail term.
Turner, described as manipulative, was ordained a Catholic priest in 1969. He began teaching at Ampleforth in the late 1970s after leaving Oxford University after just one year.
“While teaching at that school (Turner) abused a number of boys,” said Mr Storey.
The abuse began in the early 80s but it wasn’t until 1987 that Turner was “shunted out” of the school after confessing to the headmaster that he had had sexual “contact” with the named pupil.
He later admitted to the headmaster that the so-called “isolated incident” in 1987 was nothing of the sort and that he had abused several other boys at the school.
It was that confession, together with the Nolan Report, which ultimately led to the police getting involved.
The court heard that Turner took the named Ampleforth pupil ‘under his wing’ in the mid-1980s but soon seized his opportunity to abuse him during a weekend trip to a hostel in the grounds of the school.
The boy, now a middle-aged family man with a highly-successful professional career, said Turner “comprehensively” abused him during “extended sessions” at the hostel and a monastic retreat in North Yorkshire.
He was “completed dominated” by Turner, an imposing figure who abused the boy for two-to-three years.
“The defendant told him that what was happening was a secret and told him not to tell anyone,” said Mr Storey.
“He would give him sweets… and on occasions would give him alcohol, specifically altar wine.”
Turner also introduced him to pornographic material from his own “stash of porn” and taught the boy sexual techniques which developed into penetrative sex on numerous occasions.
Turner was also priest for a nearby parish in North Yorkshire where he abused the boy in the vestry. The boy once had to hide in a cupboard when a female parishioner turned up unexpectedly.
“(The victim) felt entirely unable to say anything about what was happening, even after the defendant was removed from the school,” said Mr Storey.
A friend finally persuaded him to report the abuse about three years ago.
In court this week, the Ampleforth victim said: “Gregory Carroll, Peter Turner - whoever you are or have pretended to be - to me you are a priest, a teacher, a rapist, a paedophile,” said the victim.
He recalled Turner being unwashed during the abuse and “smelling of aniseed and cigarette smoke”.
He said the debauched priest had “confused me mentally and profoundly” and made him feel like he was to blame when he was just an “innocent boy, used and sullied, humiliated and abused, raped”.
He had felt suicidal “many times” due to the priest’s “evil” acts, adding: “Nothing in my past… is not tainted by (Turner’s) insatiable and calculating need to secure opportunities for sex, using me to cover (his) tracks whilst hiding in plain sight.”
He told Turner: “What you did to me… I will have to live with until the day I die. It is just as likely that what you did to me will kill me just as much as old age or disease.”
Judge Sean Morris said Turner’s horrific offences had caused “severe” psychological harm to the victims who had been subjected to extreme humiliation and degradation.