A former teacher at an independent boys school in Richmond has been jailed for 18 years for sexually abusing 10 boys.

Patrick Vernon Marshall, 68, was found guilty of 24 counts of indecent assault and one count of sexual activity with a child on Monday, February 6, after a four-week trial at Southwark Crown Court.  He was sentenced the same day.

From yesterday: Third former teacher from St Paul's School found guilty of sexually abusing young boys

Marshall, who worked at the prestigious St Paul’s School in Lonsdale Road, Barnes, from 1971 until 1981, and targeted a number of boys at the school rowing club where he was a coach.

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St Paul's School, in Lonsdale Road, Barnes

His 10 victims were aged between 11 and 15-years-old at the time of the offences, and were vulnerable because of youth, family circumstances or low confidence. One of the boys he abused was grieving for the loss of his father.

Two of the indecent assault charges were committed when Marshall worked at Windsor Grammar School from 1968 until 1971.

According to the Metropolitan Police, Marshall gained the trust of the boys’ families to manipulate circumstances in which he could carry out his abuse.

Marshall is the third former teacher at the school to be convicted of indecently assaulted boys aged under 16.

David Sansom-Mallett, 70, of St James Road, Purley, was jailed for 14 years and nine months after being found guilty of 23 sexual offences against four boys between 1974 and 1983 at a trial at Southwark Crown Court in November 2016.

Samsom-Mallet was a master at St Paul’s preparatory school Colet Court between 1973 and 1975. Three of his victims did not attend St Paul’s School.

Michael Ellis, 71, of Bolton Road, Chiswick, was found guilty of two indecent assaults of boys under 16 between 1973 and 1992 at Southwark Crown Court in July 2016. He also pleaded guilty to four counts of making indecent images of children on his home computer.

The former sports coach, who worked at St Paul’s between 1990 and 1992, was sentenced to eight years and six months imprisonment. One of his victims did not attend St Paul’s.

The men were charged as part of Operation Winthorpe, which was launched in February 2014 after a number of allegations were made of child sexual abuse in the Barnes area from the 1960s to the 1990s.

Detective Superintendent Ang Scott, who led the investigation, said: “Patrick Marshall abused his position of trust as a teacher to take advantage of 10 boys whom he targeted over more than a decade.

"Marshall manipulated his way into the trust of the boys' families and used threats to ensure they stayed silent about the abuse.

"I would like to praise the bravery of the people abused by Marshall who, despite the passage of time, had the confidence to come forward and report the abuse to police and give evidence in court.

"Our specially trained officers have supported the people involved in this case throughout the court process and I hope the guilty verdicts give them some form of closure.

"These convictions demonstrate that, no matter the length of time, allegations of sexual abuse will be thoroughly investigated and offenders brought to justice."

Anyone with any information about others who may have been abused by Marshall, Sansom-Mallett or Ellis is asked to call police on 101. 

Anyone who has been the victim of sexual assault should contact their local police force, or call the NSPCC helpline on 0808 800 5000.