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Two guilty of young nanny's murder

News   •   May 24, 2018 11:01 BST

[Victim: Sophie Lionnet]

A couple who spun a web of lies to justify the torture and murder of their vulnerable young nanny at the south-west London home they shared have today, Thursday 24 May, been convicted of murder at the Old Bailey.

Sabrina Kouider, 35, (05.12.82) and Ouissem Medouni, 40 (25.07.77), were both found guilty after a three-month trial of murdering Sophie Lionnet from Troyes, France, on or before Wednesday 20 September, 2017, at the house where they lived with their two children in Wimbledon Park Road, SW18.

The couple, who were both French nationals like 21-year-old Sophie, had previously pleaded guilty on 12 January at the same court to perverting the course of justice by way of preventing a lawful burial of her body.

Medouni, a self-employed businessman and Kouider, a self-styled fashion designer/stylist who liked to boast of mixing with celebrities, will be sentenced on Tuesday, 26 June. The jury deliberated for 29 hours and 39 minues. There was a 10-2 majority in favour of Medouni being found guilty of murder and a unanimous verdict for Kouider.

The pair subjected naive and trusting Sophie - who cared devotedly over 18 months for their two boys aged eight and four - to months of mistreatment, threats and physical abuse that left her broken down and a virtual prisoner.

Her ordeal culminated in a series of ‘interrogations’ conducted by the duo over a 12-day period, in a bid to force Sophie to confess to various false crimes they had accused her of. Kouider recorded and filmed some of these sessions - in which she played ‘hard cop’ to Medouni’s ‘soft cop’ - on her phone, which they planned to hand them over to police as ‘evidence’ of the nanny’s guilt.

A still image of Sophie from a video on 18 September shows her with her eyes downcast, looking scared, pale and emaciated - and just two days later, on 20 September, firefighters made the horrific discovery of her body on the patio in the back garden. Medouni was trying to burn her corpse with caustic acid in a bid to eliminate any trace that Sophie had ever existed.

They might have succeeded but for a vigilant neighbour who rung the fire service on the afternoon of 20 September after becoming concerned at the excessive amount of smoke.

Firefighters arrived to discover Medouni cooking food on a barbecue in an attempt to disguise his real purpose of rendering the body unrecognisable - he had even scattered bits of cooked chicken on top of Sophie's charred body as part of the elaborate charade.

On being confronted and asked what he was doing, Medouni claimed he was ‘cooking a sheep’ but firefighters immediately suspected it was in fact human remains. It was impossible to tell the gender and age.

Medouni was arrested within half an hour of police arrival just before 18:30hrs – and Kouider later that evening after she had returned with the children and been taken to a neighbour’s house for questioning.

Kouider’s immediate attempts to mislead police were captured by the body worn video of the first officer, as she pretended she couldn't remember the surname of a nanny she had employed for 18 months, and claimed that Sophie had fled a few days beforehand for fear of the couple reporting her to police over the allegations they had levelled against her.

A post-mortem examination on Sophie’s body could not determine the cause of death and it was only weeks later, on 3 October, that Sophie was able to be identified through DNA. Kouider and Medouni were charged on 22 September.

The trial heard prosecution counsel lay out the detailed picture pieced together by homicide detectives that led to Sophie’s tragic death at some point before 20 September.

Sophie had first got the job after meeting Kouider’s brother in France, and initially things appeared to go well. However as the months went on, it became apparent to those who knew her that Sophie had been inveigled into a uniquely bizarre and oppressive household ruled by Kouider’s violent mood swings.

Other local nannies observed that Sophie seemed to think it was normal that she was barely paid, and she dropped hints over time that she was both scared and hungry. A fish and chip shop owner that Sophie had visited recalled how she had grabbed food as if starving and revealed in a fearful fashion how she was beaten.

The prosecution argued that Sophie’s timid, gentle, people-pleasing nature made her ripe for exploitation by a controlling vindictive personality such as Kouider.

The court heard that Kouider was obsessed with the father of her youngest child, her ex-partner Mark Walton, a co-founder member of the Irish band Boyzone. She accused Sophie of being in league with Mr Walton, now a music producer living in Los Angeles, to concoct a plot that would see Kouider and Medouni framed for crimes against their children and win Walton custody of his son.

It was revealed that on arrest, Kouider talked of previously making a number of allegations about Mr Walton following the end of their two-year relationship, including one of sexual abuse. No evidence was ever found to support this.

The delusions Kouider entertained around Sophie’s supposed collusion with Mr Walton - who gave evidence against her during the trial - escalated into even wilder accusations; that Sophie had obtained heroin and let Mr Walton into the family home in order to drug the family and sexually abuse the children.

Sophie herself was accused by Kouider of carrying out a sexually abusive crime against the older child, yet as police pointed out she continued to allow the nanny to sleep in the children’s bedroom and be their primary carer. Furthermore, Sophie was accused of facilitating Mr Walton taking semen from a sleeping Medouni to frame him for a future criminal charge.

The mistreatment of Sophie accelerated to the degree whereby the bullied and intimidated nanny effectively became a virtual prisoner in the house, persuaded into writing fake ‘confession’ notes that the couple hoped to use alongside their electronically recorded interrogations to persuade police they were the victims and Sophie the criminal.

Kouider’s paranoia increased in parallel with these sessions carried out at the home as she and Medouni tried to coerce Sophie into confessing that she was in love with Mr Walton and conspiring with him, shouting and swearing at her while making even more extreme claims that Sophie had enticed the two boys to go to a stranger’s house where unknown paedophiles gathered.

Handwritten notes the jury were shown written by Sophie denied she had harmed the children in any way and complained of the crude insulting names that Kouider had repeatedly called her. They included phrases such as: ‘I want to leave’ and ‘I am scared’ and begged to be given permission to visit her family in France. In a letter to her father, in June 2017 around three months before her death, Sophie also admitted to being ‘very worried’ and that she had been accused of ‘things I would never do’.

The jury heard audio of the 'interrogation' sessions and Kouider could be heard persistently berating, ranting and screaming crude sexualised insults at Sophie, rapidly switching between French and English. Medouni could be heard intervening, alternately trying to convince Sophie to tell ‘the truth’ and then that she would face prison and be barred from returning to her home country if she did not confess all.

Sophie barely made a sound on the tapes, only occasionally denying the accusations and saying ‘sorry’ or ‘no’.

On arrest, Kouider had also immediately demonstrated the pattern of intimidation against Sophie by insistently repeating false accusations against her, such as that she had stolen a diamond ring and taken Mr Walton’s son to a house where she claimed Mr Walton had said the family would be 'shot' and that the child 'would have a new mum and dad'.

Kouider had even reported the latter allegation to Kingston police in the summer of 2017. Following enquiries, the police had found no evidence to substantiate any of these allegations.

Many witnesses at the trial testified to Kouider's violent and sudden tempers, including Mr Walton who spoke of her extreme behaviour during their two years together, and who confirmed to court he had never even met or communicated with Sophie.

The prosecution successfully argued that the couple had agreed on a campaign of torture against Sophie and during the course of that campaign she was murdered. Detectives could not prove exactly how or when Sophie died and the web of lies told by both defendants was so complex it proved impossible to untangle and say for certain what had happened to her in those last hours. In cross-examination Kouider and Medouni blamed each other for Sophie's death, each telling different versions.

Detective Inspector Domenica Catino, of the Met’s Homicide and Major Crime Command, (HMCC), said: "As the investigating officer in this case I am satisfied that the verdict has bought some justice for Sophie but of course it will never bring her back. 

"I cannot imagine what thoughts were going through Sophie’s mind whilst being held a prisoner in those 12 days leading up to her death but from the harrowing images obtained it showed a scared, broken and emaciated young girl who probably knew she was shortly facing death.

"I believe that we are Sophie’s voice telling of the torment, abuse and torture she suffered and today she has finally been heard.

"This has been an extremely harrowing and tragic case. Both Ouissem Medouni and Sabrina Kouider have robbed Sophie Lionnet, who was only 21, of her promising life and took her from her family and friends, who will never again get to see a beloved daughter, sister and friend.

"We will never know the full extent of the horrors Sophie had to endure as not all the ‘interrogations’ were recorded. Even in death the torture, abuse and humiliation continued by placing her partially-clothed body into a suitcase with no regard for even a semblance of a burial, before taking the callous decision to burn her in an attempt to hide their murderous act.

"Again during the trial the abuse and humiliation of Sophie continued as Kouider portrayed herself as the victim and made wild accusations against Sophie and her mother. It was clear that together the couple made the decision to torture Sophie and then in a cowardly fashion blamed each other for her death. They were determined to do whatever it took to get what they wanted and neither one took any steps to help Sophie, it was always about them.

"By Kouider and Medouni burning Sophie’s body to such an extent, it deprived her family of seeing her to say their goodbyes. No-one has the right to take that away from a mother or father, again it shows the cruel, evil nature of Kouider and Medouni - there were no boundaries for these two; no humanity, no compassion.

"I cannot praise Sophie’s family enough for their support and dignity maintained throughout the trial. I have personally seen their suffering, and they are the ones who are really serving a life sentence.

"I would like to thank the French Embassy and consulate for their assistance along with those involved in the prosecution. I would also like to highlight the excellent work of my investigation team and commitment in getting justice for Sophie."