Detective jailed for murdering partner and burying her in a woodland grave

Foster had previously pleaded not guilty to killing Detective Constable Heather Cooper, 33, who was stabbed before her body was dumped in Blackdown Woods, near Lurgashall, West Sussex, in October last year.

But the 36-year-old former detective constable, who lived with the mother-of-two in Haslemere, Surrey, changed his plea to guilty at Lewes Crown Court today.

Miss Cooper was killed at the couple's home while she was on maternity leave with her second child, who was born just weeks prior to her death.

The court heard that Foster claimed Miss Cooper had attacked him and he initially acted in self-defence but then his actions turned to aggression.

The hearing was told he hit her over the head 10 times with a baseball bat before stabbing her in the throat.

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The court was also told that Foster did not have a clear memory of the events.

Miss Cooper, who grew up in York, joined Surrey Police in 2003 and worked in the Public Protection Investigation Unit based at Guildford police station.

During her career she received several letters of praise from senior officers for her work on various crimes and in 2009 was given a commendation by the force for her "professionalism, dedication and commitment".

Sentencing Foster, Judge Richard Brown described him as an "extremely dangerous individual" who may never be safe to be let out of prison.

He said: "This was a wicked, savage and senseless attack on a young mother in her own home.

"Not only have you taken her life, you have also deprived Joshua and Isabel of a loving mother and, no doubt, devastated her family and friends."

The judge added that aggravating factors were that the attack was carried out in front of the couple's children, that the defendant was trained in martial arts, and the ferocity of the attack which involved two weapons.

He said the minimum prison term would be 17 years but it would be a matter for the parole board whether Foster would then be released.

He told him: "Whether or not you will ever be released will be a matter for them.

"Many matters may point to you being an extremely dangerous individual. However, that's a matter for the parole board, not me."

Benjamin Aina QC, prosecuting, told the court Foster carried out the attack in front of the couple's two young children, Joshua, now three, and Isabel, who was only three months old at the time.

He said the family attended the Christening of the grandchild of a friend, Steve Potts, on the morning of October 16, but an argument flared when their baby bag, containing a camera and nappies, was mislaid.

The couple sat with their backs to each other in the church and they left early without attending the reception.

Mr Aina said the disagreement persisted throughout the afternoon, during which time Foster left the house to buy two bottles of wine, some of which he then drank.

After returning to the house, Foster claimed Miss Cooper swiped at him with a knife while he was carrying Isabel and while Joshua was also in the room.

He told police that, in self-defence, he hit her once with a baseball bat. She then left the room and he later found her with a knife through her throat.

But Mr Aina said the post-mortem examination showed that Miss Cooper had been hit more than 10 times with the bat and the stabbing would have happened after she was unconscious and after she had been knocked on to the sofa.

He added that Foster had three knife injuries to his hand which was inconsistent with his account that Miss Cooper had attacked him with a single swipe and instead suggested they may have been self-inflicted.

Mr Aina said Foster was known to have a "short fuse" and had lost his temper, leading to his partner's death.

He said: "On many occasions Mr Foster had lost his temper on trivial matters and gone over the top.

"The violent attack is another indication of another over-reaction on his part, this time with tragic consequences."

Mr Aina said Foster took time to clean up the blood-soaked crime scene and took Miss Cooper's body to the woodland, where he covered it with bracken.

He also made several trips to the home of his grandmother, Marguerite Halkins - who had brought him up - to take the two children to her.

He also told his cousin, David Foster, some of the details about what happened, leading him to alert the police.

The court heard that officers attended Mrs Halkins' house that evening and Foster told them: "You should arrest me." When they asked him what for, he replied: "Murder."

The court heard he then led officers to where he had hidden Miss Cooper's body.

The court heard that Foster sent a number of text messages on the afternoon he killed Miss Cooper in a bid to create an alibi for himself.

He concocted a story that she had found out he had been having an affair and was leaving him.

In one message to Mr Potts, a retired police office, he wrote to apologise that they had left the Christening early.

He wrote: "Sorry mate, keep it to yourself, Heather and I are on verge of break-up over very serious lies she had been doing. Sorry for not being there."

Mr Potts replied: "Mate, sorry to hear that, as always here for you if you need to meet up and have a chat. Let me know."

Foster was to reply: "We talking, call you this evening."

But this was a lie as Miss Cooper was already dead, according to Mr Aina.

Foster, who worked as a plumber after leaving the police, also sent a message to a colleague which said: "Hi mate, Heather walked out on me. Explain later. Left me with the kids. Please can you cover tomorrow?"

And he told another friend, Anthony Crowie, on the phone that: "Heather found out I was cheating on her and has left me."

Foster also sent two messages to Miss Cooper's mother, Caroline, stating that her daughter was still alive.

The first said: "Congratulations" and the second said: "Sorry Caroline, sent to wrong person. Been to Christening today, hope all is well with you."

He then sent one from Miss Cooper's mobile phone, pretending to be from her, which was meant to reassure her mother that everything was OK, according to Mr Aina.

Philippa McAtasney QC, defending, said that Foster, who had been married previously, had expressed "genuine remorse" over what he did.

She explained that he had made a "serious" attempt to commit suicide while on remand and was currently staying on a mental health wing of the prison.

She said that he had over-reacted after Miss Cooper had initially attacked him.

She said: "Peter Foster must live with the fact he killed the woman he loved, the mother of two of his three children, and he knows he has ruined all of their lives and knows that nothing he can say can undo the pain and the hurt that everyone feels.

"There's no excuse or justification for taking Heather Cooper's life."

She added: "This had started as a silly argument between them which had escalated and had culminated in Heather Cooper picking up the kitchen knife."

Miss McAtasney said that Mr Foster's life spiralled downwards after his father was murdered in Sierra Leone.

She said this led to him drinking and he was caught driving over the limit which put an end to his police career.

The court heard that he was sentenced to six months' imprisonment, suspended for a year, at Portsmouth Crown Court in May 2010 for offences of drink driving and dangerous driving.

The hearing was told it was this conviction that led to him resigning from Surrey Police.

Foster's father, Nick Foster, was shot dead during an armed robbery in Freetown, Sierra Leone, in 2009.

Miss McAtasney said: "He had just reformed a relationship with his father and they were very close when he was murdered in Sierra Leone.

"Because of that he went off the rails, because of that he tried to take his own life and he ended up appearing in front of Portsmouth Crown Court.

"It was as a result of his father that he resigned from the police service.

"Prior to that he had served the community while in that capacity for something like nine years."

In the statement, Mr and Mrs Cooper, who did not attend court, said: "Through her death, Heather lost her children for 50 years of her life, Joshua and Isabel have been given a life sentence by the loss of their devoted mother.

"Heather would have been devastated to know she would not be able to bring up her children and Isabel would never know her mummy and Joshua would suffer grief at such a young age.

"Joshua was present when his mother was brutally murdered.

"We cannot envisage what he is currently experiencing and what is going on in the mind of this three-year-old."

The statement said the death had devastated the family, making it impossible for them to support others, including Miss Cooper's brother who lived in Australia.

They also said Mrs Cooper's mother died shortly after her grand-daughter.

The statement said: "Caroline's mother was left devastated and stated several times she had no more interest in living.

"It's ironic she died very shortly afterwards, with Caroline unable to give her the support she needed at the time of her death."

The statement concluded: "The emotional effect of Heather's death has been widespread.

"The impact on the community has been widespread. Friends and colleagues have said that their lives would never be the same again.

"We would never have envisaged that one man's savage attack on a slight woman could have had so much impact on so many people's lives."