'Morally reprehensible' officer who sexually assaulted child on duty sacked and barred from service

We have sacked a serving officer at an accelerated misconduct hearing following our investigation into them sexually assaulting a child while on duty.

PC Dean Dempster (35), who was a response officer based at our Oldham district, was today (2 May 2024) dismissed without notice, and added to the College of Policing Barred List by Chief Constable Stephen Watson, who described Dempster’s actions as “morally reprehensible”.

The hearing at GMP Headquarters is our latest use of accelerated proceedings as part of our pledge to ‘root and boot’ more officers unfit to serve the public more quickly.

Since 2021, we have ensured we have sped up this process with almost four times as many accelerated hearings being held in the most recent 12-month period.

We will now be writing to the Deputy Mayor of GM to appeal for Dempster to lose his right to a police pension. 

Presiding over today’s hearing, CC Watson found PC Dempster’s conduct amounted to gross misconduct, saying: “This sexual assault occurred whilst the officer was on duty and where the victim was totally trusting and reliant on him performing his duties professionally, compassionately and with her welfare uppermost in his thoughts. 

“It is this most egregious breach of trust of an innocent young child that is most upsetting aspect of this case and something that clearly amounts to an aggravating factor. 

“I consider this case to be among the most distressing ever presented to me such is the despicable betrayal of all that is inherent in being a decent police officer. 

“I have no hesitation whatsoever in dismissing PC Dempster from the service with immediate effect.”

Dempster was convicted of sexually assaulting a young girl while responding to an incident on 29 December 2023. We received a complaint later that day and he was promptly arrested by a supervisor on the district when he returned to duty the day after.

Our unit dedicated to professional standards conducted an investigation – directed by the Independent Office for Police Conduct – which led to his conviction at Liverpool Crown Court in February. He has remained suspended since being swiftly charged on 31 December 2023.

Detective Chief Superintendent Mike Allen, head of our Professional Standards Directorate, said: “Dean Dempster is not a police officer, he’s a child sex offender who has no right to be in police uniform or in a position to serve the public.

“We have no time for people like Dempster who should not be in GMP and does not represent us.

"This is why we’re increasingly using accelerated misconduct hearings to root out and boot out officers who are unfit to serve in our uniform, and this work will continue while ever they remain.”