A former Royal Navy petty officer already serving a life sentence for the murders of two young men has been sentenced to a further 22 years' imprisonment after he was convicted of a series of non-recent sexual offences.

Allan Grimson, 66, was found guilty by a jury at Winchester Crown Court of offences committed between 1994 and 1999 against a teenage boy and young Royal Navy recruits.

Grimson, who served as an instructor at the Royal Navy Firefighting School at Horsea Island, used his position to target and sexually abuse boys and young men over a number of years. Victims included a 14-year-old boy and young servicemen at the start of their naval careers. Today, 6 November, he has had 22 years added to his sentence.

The convictions followed a review of allegations dating back more than 20 years, including a case reconsidered following a referral to the Child Sexual Abuse Review Panel.

After reviewing the evidence, the Crown Prosecution Service authorised charges against Grimson.

Grimson is already serving a life sentence for the murders of Royal Navy ratings Nicholas Wright and Sion Jenkins, whom he killed in 1997 and 1998 after meeting them in Portsmouth. They were both sexually assaulted before they were murdered.

James Foster, Specialist Prosecutor, of the Crown Prosecution Service, said: "Today’s sentence reflects the seriousness of Allan Grimson’s offending and the profound impact his abuse had on victims over many years.

"While cases like these can present unique challenges of their own, this conviction has demonstrated that the passage of time is not a barrier to delivering justice for victims of non-recent sexual abuse – and allegations will be pursued wherever there is sufficient evidence to support a prosecution. 

"Following a referral to the Child Sexual Abuse Review Panel, we carried out a fresh review of two of the original decisions in this case and concluded that criminal charges should be brought.

"I would like to pay tribute to the victims for the courage and determination they have shown throughout this process. We hope today’s sentence provides some measure of justice and recognition for the abuse they suffered, and encourages other victims and survivors to come forward knowing they will be listened to and taken seriously."

Building the case

Police arrested Grimson in December 1999 during the investigation into the disappearance of Royal Navy rating Nicholas Wright. Searches of Grimson's Portsmouth flat and family addresses uncovered photographs and evidence linking him to a number of young males.

Among the material recovered were indecent photographs of a child and images involving another of the complainants. During police interviews, Grimson identified individuals shown in the photographs and admitted sexual activity with some of the victims.

The prosecution case centred on four victims. Grimson befriended young males he met through the Royal Navy and personal connections before sexually abusing them. Several offences took place at his Portsmouth flat.

Jurors heard evidence from victims who described being abused while asleep, intoxicated or too frightened to challenge Grimson's behaviour. One victim told police he only felt able to come forward after Grimson had been imprisoned because he finally felt safe.