Warrant Officer Michael Webber, 43, previously pleaded guilty to the attack on Royal Artillery Gunner Jaysley Beck, 19, during a stay at Thorney Island, near Emsworth in Hampshire, in July 2021.
He appeared before Bulford Military Court Centre on Friday and was sentenced by the Judge Advocate General Alan Large and a military board.
During the incident, Webber engaged Gunner Beck in a drinking game called Last Man Standing before touching her thigh and trying to kiss her.
Gunner Beck pushed Webber, then a 39-year-old battery sergeant major, away and spent the night locked in her car before making a complaint to her superiors in the morning.
However, the incident was not reported to police and Webber wrote a letter of apology to Gunner Beck, from Cumbria.
She was found hanged in her room at Larkhill Camp in Wiltshire at about 4pm on December 15 2021 – five months after the incident.
At the conclusion of her inquest in February 2025, Assistant Coroner Nicholas Rheinberg ruled that the Army’s failure to take appropriate action made a “more than minimal” contribution to her death.
Judge Large told Webber: “At some point in the early hours of July 13, you told Gunner Beck she was beautiful, you put your hand on the back of her head, you leant in to kiss her and you touched her thigh.
“She had the courage and good sense to tell you to stop and told you to go to bed, but you persisted to the extent she considered she wouldn’t be safe from you even if she went back to her own accommodation.”
He continued: “The next morning, she reported the incident to her family, her friends and her chain of command. Following the report, the unit decided to deal with you with minor administrative action.
“You were interviewed and you accepted your behaviour had been unacceptable. You wrote a letter of apology.
“Your career continued completely unaffected and you were in due course promoted to Warrant Officer 1.”
The judge told Gunner Beck’s family the sentencing was part of the process for dealing with what happened to her during her time in the Army.
He told Webber he would serve half his sentence in custody, and put him on the sex offenders register for seven years.
Prosecuting, Commodore James Farrant told the military court on Friday that Webber and Gunner Beck had been away for adventure training on Thorney Island when the incident took place.
He said: “On the first night of their training, both of them stayed up in the bar drinking and in fact the two of them were the last two present in the bar.
“At some point, after they had been drinking together for some time, Mr Webber told the complainant that she was beautiful.
“He put his hand on the back of her head in order to kiss her and he also touched her thigh. She asked him to stop and told him that he should go to bed.
“However, he continued to the extent that Gunner Beck feared she would not be safe from him if she went to her accommodation.”
The court heard Gunner Beck first hid in the toilets, standing on top of a toilet seat so Webber would not see where she was, before locking herself in her car overnight.
She reported the incident the following day and Webber was dealt with by a minor administrative action – involving him being interviewed and writing Gunner Beck a letter of apology.
Commodore Farrant said: “I am sure this court will find that whatever its justification at the time, it was not appropriate that this incident was dealt with administratively.
“It meant no police investigation could take place.”
He added that a service inquiry later found Gunner Beck had been subjected to a “number of inappropriate behaviours by personnel senior to her in the months before her death”.
During her inquest, it emerged Gunner Beck had received thousands of messages from another senior colleague, Bombardier Ryan Mason.
Wiltshire Police investigated a complaint of harassment submitted by Gunner Beck’s family after her death, relating to Mr Mason’s behaviour, but found the evidence did not support a criminal harassment case.
The force also investigated the incident involving Webber but declined to refer it to the Crown Prosecution Service, Commodore Farrant added.
Following Gunner Beck’s inquest, Wiltshire Police transferred jurisdiction of the case to the Defence Serious Crime Unit and the Service Prosecuting Agency charged Webber with sexual assault in August.
He pleaded guilty to the charge on September 5.
Victim personal statements written by Gunner Beck’s mother Leighann McCready, father Anthony Beck, and sister Emilli Beck were read to the court.
Ms McCready described how she received a phone call from her “very upset” daughter following the incident, who had been “very scared” by Webber.
“My bright, confident daughter became quiet and withdrawn,” she said.
She described how Gunner Beck felt powerless by how Webber was dealt with, later discovering he had been promoted to Warrant Officer Class 1 rank – telling her “I got a letter, he got a promotion”.
“The assault shattered her faith in the system that was supposed to look after her,” Ms McCready said.
“I truly believe that what he did and how it was handled broke something inside her that she couldn’t repair.”
Mr Beck told how Webber was a man of large build in a position of authority who had assaulted his daughter, who had just turned 19.
“Knowing that someone like him could sexually assault my baby makes me feel sick to my stomach,” Mr Beck said.
“She was only 19. I could see what he had done completely changed her. It broke me to see that light go out in her.”
Miss Beck paid tribute to her younger sister as “confident, career driven and always her authentic self”.
“Jaysley called me that day after the incident and explained the actions of Michael Webber,” she said.
“She was disgusted. Michael Webber had severely frightened her that night.”
Miss Beck described herself as “repulsed” at Webber’s actions, adding “a man who was old enough to be her father had taken advantage of her”.
The court heard Webber, who is divorced with an estranged teenage daughter, served in the Army for 22 years and 128 days before leaving in August this year.
He now works as a lorry driver.
Representing Webber, Matthew Scott said: “He is devastated by what happened to Miss Beck.
“He doesn’t seek to shy away from his responsibility for what happened, he accepts through me that his actions on that night on Thorney Island contributed in some way to the tragic outcome when she took her own life in December, about five months later.”
Mr Scott said the Army’s service inquiry report published in October 2023, and the inquest identified “many other reasons which contributed to Miss Beck taking her own life in the way she did”.
He added that his client, who the court heard receives £1,200 per month from a military pension, had an “exemplary military record” and described the incident as “out of character”.
