It is the latest example of a classic case of ‘folie à deux’: the madness of two. In other words, a shared psychotic disorder that usually involves one dominant person convincing the other of their beliefs. French au pair Sophie Lionnet was murdered by Sabrina Kouider (in this case, the main force behind the killing) and Ouissem Medouni.
Lionnet was starved and tortured by the couple, her body then burned in the garden of their home in London.
By committing this murder, Kouider and Medouni have joined the ranks of killer couples: the partners that go on to commit their crimes together. They also comprise some of the most notorious murderers of which we know.
Rosemary and Fred West are one of the most famous examples and two of Britain’s most notorious killers, active between 1967 and 87. Fred was a sexual deviant who had already raped and killed before he met Rosemary.
Rose was the perfect match: a woman who not only went along with his crimes, but could convince young women to return to the pair’s home in Gloucester. The girls would be kept captive in the basement of their home, where the couple would rape and torture them. When they tired of their victims, they would kill and dismember them, burying their remains in or near their house. By the time police had obtained an arrest warrant for their home, the pair had killed at least 12 victims, including two of their own daughters and allegedly, Fred’s first wife. Fred was charged with 12 murders; Rose, 10. He committed suicide in prison before his trial, while Rose was sentenced to life imprisonment.
Equally infamous are the Moors murderers Ian Brady and Myra Hindley. Active between 1963 and 65, the pair killed five children, all between the ages of 10 and 17. Brady and Hinley met at work when Myra was 18. She quickly became infatuated with him and the pair started dating. In 1963,
Brady began talking about committing the perfect murder and in 1963, they killed their first victim: Pauline Read. As with the Wests, Myra was the one responsible for luring the victims in after Ian chose them. Over the next two years, the pair would kill four other children, sexually assaulting, torturing and then brutally murdering them. Their bodies were buried on the Saddleworth Moors. The two were convicted for their crimes and Myra died in prison in 2002, while Ian died in Ashworth Hospital in 2017.
Similar crimes were committed in Canada by Karla Homolka and Paul Bernardo, known as the Ken and Barbie killers. A young couple that met in the 1980s when Karla was 17 and Paul 23, Paul was already raping women before he met Karla, becoming known as the Scarborough Rapist.
Karla encouraged him and the pair went on to kill at least three young women. The first was Karla’s sister, Tammy. Karla had promised Paul Tammy’s virginity as a ‘present’. The two drugged Tammy, then Paul raped her while Karla filmed the act. Tammy began to choke on her own vomit and though the couple called 911, paramedics couldn’t revive her. After Tammy, the couple brutally raped and murdered 14-year-old Leslie.
It’s not always the man that is the dominant within the relationship. Elizabeth Haysom was 22 when she met Jens Söring at the University of Virginia in the 1980s.
Together, the pair brutally murdered Haysom’s parents, almost decapitating them, so violent was the killing. They then fled to England, where they were arrested for fraud. Haysom was diagnosed with borderline personality disorder, while Söring, folie à deux.
Elizabeth pled guilty to two counts of murder before the fact and was sentenced to 90 years inside. Although Jens originally confessed, he recanted his statement and said it was Haysom who had committed the crimes and he had simply taken the blame. Additionally, it was Söring’s confession, rather than the evidence, that enabled prosecutors to charge him. None of the DNA found at the scene was his. However, he was convicted of two counts of first-degree murder and sentenced to life imprisonment.
In a similar case, 12-year-old Jasmine Richardson persuaded her 23-year-old boyfriend Jeremy Steinke to kill her parents and younger brother. The two fled the scene but were arrested. Steinke was given three life sentences, while Richardson finished her 10-year sentence in 2016. Although as Steinke also believed he’s a 300-year-old werewolf, what are three life sentences?
One particularly violent pairing was that between Henry Lee Lucas and Ottis Toole. After the two drifters met in 1976, the pair were said to have committed 108 murders together, although Lucas confessed to over 3,000. Both were sent to prison, where they each died.c
Nor is the shared madness restricted to couples, as the Eriksson twins proved. Swedish sisters Ursula and Sabina came to England in 2008, travelling on a bus to London. However, during a stopover, the pair acted so strangely, the driver refused to let them back on the bus. They were then caught on CCTV walking down the M6 motorway and attempting to cross it, causing chaos and leading to Sabina being hit by a car.
The police were called and detained the sisters, but while they were there, Ursula managed to escape and ran into the path of a lorry. Sabina then followed and was hit head-on by another car. Both survived the incident, but resisted medical help, Sabina hit an officer and then ran into traffic again. It’s still not known what caused their behaviour