Former GMP officer jailed for nine years for sexually assaulting young girl while on duty
A video report from ITV Granada Reports Journalist Jennifer Buck
A former Greater Manchester Police (GMP) officer has been jailed for nine years for assaulting a vulnerable young girl while on duty and superimposing his face onto child abuse images.
Dean Dempster, 35, who was based in the Oldham division of GMP, sexually assaulted the little girl while responding to a disturbance in Oldham on 29 December 2023.
The following day Dempster, from Manchester, was arrested at work following a discussion about a formal complaint against him, and his personal phone and work phones were seized.
It later became apparent that before his arrest that morning, Dempster had deleted some material and applications from his personal mobile phone.
Following a search of his home, police uncovered another iPhone, a bundle of four pairs of folded children’s underwear, shredded underwear in a bag, a disc of images, and two hard drives.
Dempster’s mobile phone and iPad were found to contain 104 indecent images of children graded as category A – the most serious – including 30 pseudo images of that level as well as 440 category B images, including 129 pseudo images, and 2,472 category C images, including 39 pseudo images.
A large number of the pseudo images had been superimposed to depict Dempster with children.
The examination of his devices suggested that Dempster had been downloading indecent images of children over a two year period – between 15 December 2021 to 29 December 2023.
Following an accelerated misconduct hearing in May 2024, Dempster was sacked by the force.
He previously pleaded guilty to one count of sexual assault on a child under 13, six counts of making indecent images of children and two counts of misconduct in public office.
The prosecution followed an investigation by GMP’s Professional Standards Directorate directed by the Independent Office for Police Conduct.
On Wednesday 13 November, at Liverpool Crown Court, Dempster was sentenced to nine years imprisonment.
GMP Deputy Chief Constable Terry Woods said: "My thoughts go out to the two victims, their families and friends.
"Myself and all my officers are angry, we are disappointed and we are completely shocked. In my 29 years of service, I have not seen an incident as such as this – an on duty uniform officer assaulting a child.
"That's why he was arrested very quickly, he was charged very quickly, he was sacked very quickly and he is about to spend a significant amount of time, as a pedophile, sat in prison cell."
Malcolm McHaffie, Head of the Crown Prosecution Service’s Special Crime Division, said: “Dean Dempster’s actions were abhorrent, and he betrayed the trust placed in him as a serving police officer.
“The sexual assault took place while he was on duty, and there is no doubt that the victim has been deeply affected by being targeted by someone in authority.
“Subsequent searches of Dempster’s devices and his home address revealed further deplorable offending, and he is now facing the consequences of his actions.
“The Crown Prosecution Service will not hesitate to bring charges against those who abuse their position and target young people in such a reprehensible way.”