Monique Olivier lived at the side of Michel Fourniret from 1987 until their separation in 2004, a marriage she later described as years of fear. Fourniret was the man French and Belgian newspapers called the "ogre of the Ardennes." She did not stand trial as a killer. Three French assize courts, sitting in 2008, 2018 and 2023, judged her as his accomplice, and each time they convicted her. The first court found her guilty of complicity in four of the murders for which Fourniret was jailed for life. The second added a 20-year sentence for her part in the killing of Farida Hammiche. The third, sitting at Nanterre after Fourniret had died, tried her alone for three cases he had confessed to but never answered for in court: Marie-Angèle Domèce, Joanna Parrish and Estelle Mouzin.
Her own statements shaped the case from the beginning. After the couple's arrest in 2003 she began describing to investigators a series of killings from the late 1980s, then withdrew parts of her account, then confirmed it again. In 2019 she undid the alibi that had kept him out of the Estelle Mouzin inquiry for years. Whether she was a frightened and dominated wife or a willing partner was argued at every trial. The courts' answer, three times over, was that she was guilty.
Little about Olivier's early life has been reported in detail. At her 2023 trial she described a lonely childhood, according to Agence France-Presse. With her first husband she had two children. He was violent, and in the early 1980s she fled him, AFP and CBS News reported. In court she was asked why she had been able to leave that man but not Fourniret. "I am incapable of managing on my own," she said, adding that she did not know why she had stayed with Fourniret so long.
Slate.fr reported that she worked as a home carer for elderly and disabled people. In 1987 she answered a small advertisement in Le Pèlerin, a Catholic weekly. It had been placed by a prisoner and read, in French, "Prisoner seeks contact to break the solitude." The prisoner was Michel Fourniret.
Fourniret was born on April 4, 1942, in Sedan, in the French Ardennes, AFP reported. He trained as a fitter and mechanical draftsman, married three times and had five children. Before he met Olivier he had already been convicted in 1967, 1984 and 1987 for assaults on about a dozen girls and young women. On June 26, 1987, he was sentenced to five years in prison, and he was serving that sentence when the correspondence began.
The two exchanged 217 letters, some 760 pages in all, according to Slate.fr. Investigators and courts later read those letters as the record of a pact. As reported by Public Sénat, the French Senate's broadcaster, and by AFP, the arrangement was that she would help him find a young virgin, and in return he would kill her violent first husband. He never harmed the first husband. At her 2023 trial Olivier denied that there had been any "criminal pact" and dismissed the letters as the correspondence of teenagers. Asked what the promises in them meant in practice, she was silent at first and then said she had obeyed him in everything.
Fourniret was released in October 1987, the Belgian public broadcasters VRT and RTBF reported, and the two settled together in the Yonne department, near Auxerre. Their son was born in 1988, and they married in 1989, according to an AFP chronology. (A Swiss report in Blick gave 1987 as the year of the marriage.)
The crimes for which Fourniret was convicted in 2008 began soon after his release. AFP and Public Sénat reported that Isabelle Laville, 17, was killed about two months after he left prison. She disappeared in late 1987. Slate.fr gave the date of her abduction as November 11, 1987. At her 2023 trial Olivier said that Fourniret had used her as bait in some abductions, among them that of Isabelle Laville, and that she was pregnant with their son at the time.
Over the next years the Ardennes court's case grew to seven murders of girls and young women, aged from 12 to 22 according to The Connexion, committed in France and Belgium between 1987 and 2001. The victims named in reports of the case are Isabelle Laville, Fabienne Leroy, Jeanne-Marie Desramault, Elisabeth Brichet, Natacha Danais, Céline Saison and Mananya Thumpong. Elisabeth Brichet was 12 when she was taken at Saint-Servais, near Namur, in 1989, VRT reported; she was the Belgian victim among the seven. Reports of the 2008 trial did not give a full account of each girl and young woman, and little else about their lives appears in the coverage.
Olivier was not charged with all seven. The court convicted her of complicity in four of the murders, together with other charges.
One killing from 1988 stood apart from the others. That year a former cellmate asked Fourniret to recover gold hidden by a robbery gang known in France as the "gang des postiches," according to AFP. Farida Hammiche, the cellmate's wife, was 30. She was killed in 1988 near Clairefontaine, in the Yvelines department, by Fourniret's own confession, and the couple kept the gold, AFP reported at the time of Olivier's 2023 trial. Her body has not been found. Public Sénat described the case as a crime of greed, unlike the killings of girls and young women for which Fourniret was best known.
For years the Hammiche case was not tried. It reached court only in November 2018, three decades later.
By 2003 the couple were living in Belgium, near the French border, RTBF reported. Fourniret was later jailed for life for killings that ran to 2001, and investigators reopened other unsolved cases in France and Belgium, 17 of them according to Slate.fr. Two of those cases came back into the Olivier file much later: the disappearance of Lydie Logé, 29, a mother of a seven-year-old boy, in December 1993 at Saint-Christophe-le-Jajolet in the Orne department, and the disappearance of Estelle Mouzin, 9, on January 9, 2003, at Guermantes in Seine-et-Marne, east of Paris.
The end came in Belgium. On June 26, 2003, Belgian police arrested Fourniret after the attempted abduction of a 13-year-old girl near Ciney, in the province of Namur. She escaped, and a motorist noted the registration of the van, RTBF and VRT reported.
Olivier was drawn into the inquiry with her husband. About a year after the arrest she began to talk. Accounts differ on how many crimes she described at first. Slate.fr said she named eight, The Connexion that her account grew from six to eight and then ten, and AFP and Public Sénat that in 2004 and 2005 she told investigators about eleven murders. RTBF reported in 2026 that in July 2004 both she and Fourniret confessed to the abduction and killing of six girls and young women in France and Belgium between 1988 and 1990. After the arrest, VRT reported, she accused him of nine murders, including that of Farida Hammiche. Fourniret admitted eight killings.
The investigation crossed the border. Belgian investigators at Dinant heard her in 2005 about Marie-Angèle Domèce and Joanna Parrish, RTBF later reported, and she told them that Fourniret had been obsessed with Domèce. Belgium handed Olivier over to France in 2005, the Associated Press reported.
Not everything in those years went smoothly. Olivier accused the prosecutor in Charleville-Mézières of hitting her during an interrogation, RTBF reported. The French courts dismissed her complaint, but the prosecutor stepped away from the case before the 2008 trial.
The trial opened on March 27, 2008, before the assize court of the Ardennes at Charleville-Mézières, near the Belgian border. Fourniret and Olivier, then 59, were tried together. The Associated Press reported that the trial was expected to last until May and that hundreds of journalists had come to follow it.
The verdict came on May 28, 2008. Fourniret was convicted of seven murders and of three attacks on girls and young women who escaped, and sentenced to life imprisonment with no possibility of release, VRT and AFP reported. Olivier was convicted of complicity in four of the murders and of other charges, and sentenced to life imprisonment (réclusion criminelle à perpétuité) with a période de sûreté of 28 years. A période de sûreté is a minimum term during which no form of release can be considered. Fourniret said he would not appeal, and no appeal by Olivier was reported.
The Ardennes case changed French police practice. Al Jazeera reported that it led to better coordination between investigators in serial cases. Alain Behr, a lawyer for Isabelle Laville's family, spoke of "a lost opportunity to identify the Fournirets." When she disappeared, Al Jazeera reported, Fourniret had just been released on probation and lived a few kilometers away, and police recorded a kidnap report without opening an inquiry.
The couple divorced in 2010. Blick gave the month as August.
Two of the cases Olivier had described in Belgium were not tried in 2008. Marie-Angèle Domèce disappeared on July 8, 1988, in the Auxerre area of the Yonne. AFP and other reports give her age as 18 or 19. Joanna Parrish was a 20-year-old British student, a French student at Leeds University working as an English language assistant at a school in Auxerre. She was killed in the Yonne in May 1990.
After the 2008 trial these files went to Paris. Investigating judges there closed the case against the couple for lack of evidence in 2011, RTBF and AFP reported. Corinne Herrmann, a lawyer for Domèce's family, objected that the couple had already been convicted of seven murders and that all the elements were present. In 2012 the Paris judge Sabine Khéris reopened the inquiry and ordered work that police had never done. RTBF reported that Domèce's friends and family had not been questioned by police when she disappeared.
In February 2018 Fourniret confessed to both killings to the judge, after denying them for years. That June, during several days of questioning in Paris, Olivier withdrew her earlier retractions and confirmed what she had said in 2004 and 2005, her lawyers told AFP. "It is a great relief for families who have been waiting for an answer for so long," the families' lawyers said.
The Hammiche trial opened on November 13, 2018, before the assize court of the Yvelines at Versailles. Fourniret and Olivier sat in the dock together again. Olivier was tried for complicity and for recel, receiving the stolen gold, and through her lawyer, Richard Delgenes, she acknowledged all the facts against her, AFP reported. Fourniret admitted the killing but denied knowing where the gold came from.
On November 16, 2018, the court sentenced Fourniret to a second life term. Olivier was sentenced to 20 years, VRT, Slate.fr and AFP reported. Reports of the verdict described her conviction as complicity in the murder.
Estelle Mouzin was nine when she disappeared on January 9, 2003, in Guermantes, about 30 kilometers east of Paris. The Versailles criminal brigade took the case the next day, and a judicial investigation was opened on January 20, 2003, according to the 2025 judgment of the Paris court. Fourniret's name came up after his arrest in Belgium that June, but he had an answer. On the day Estelle disappeared, he said, he had telephoned his son from home in Belgium, some 250 kilometers away, to wish him a happy birthday. The son had not picked up, but telephone records confirmed that the call was made. On that basis investigators ruled him out in early 2007, RTBF reported. Olivier was questioned in 2003 and 2005, and in November 2007 both she and Fourniret denied any link to the case, the Paris court recorded. An analysis of thousands of hairs from his car found no trace of the girl, and when he was questioned again in late 2017 he still denied any involvement.
The case moved when it reached Sabine Khéris, the Paris investigating judge who had reopened the Domèce and Parrish files. On November 21, 2019, Olivier was questioned by her for almost three hours. According to her lawyer, Richard Delgenes, she said that on January 9, 2003, she had made the call to Fourniret's son herself, at her husband's request. A judicial source told AFP that Fourniret had not been with her when he asked her to make it. The alibi collapsed. After the hearing Olivier was given the status of témoin assisté, an assisted witness, a step short of being charged. Delgenes said she had not said where Fourniret was that day, only that "we know that at the time Michel Fourniret used to go away for several days."
On November 27, 2019, Fourniret was charged (mis en examen) with abduction and sequestration followed by death in the Mouzin case. On January 24, 2020, Olivier was questioned by Judge Khéris for about six hours and repeated her accusation that he had killed Estelle. She gave three reasons, RTBF reported: the girl matched the victims he looked for, he had no alibi, and she believed he had scouted places in the days or weeks before. In March 2020 Fourniret acknowledged his involvement.
On August 21, 2020, Olivier herself was charged as an accomplice, the Paris court recorded. In August 2020 her lawyer told a news conference that she had told the investigating judge that Fourniret had killed the girl on the day she disappeared. In 2021 Olivier acknowledged for the first time a role of her own in the girl's confinement, AFP reported. The Paris judgment records that she admitted making the alibi call and taking part in the girl's confinement. Repeated searches in the Ardennes have not found Estelle.
Fourniret was charged on December 22, 2020, in the Lydie Logé case as well, with abduction and sequestration followed by death. He was never tried for it, or for Domèce, Parrish and Mouzin. He died on May 10, 2021, aged 79, in the secure unit of the Pitié-Salpêtrière hospital in Paris, while serving two life sentences, VRT and AFP reported. "If those people had not crossed my path, they would still be alive," he had told investigators, in an interrogation consulted by AFP.
His death left Olivier as the only person charged in the Domèce, Parrish and Mouzin cases, Belga reported.
The Mouzin case moved to Nanterre in March 2022. The tribunal judiciaire of Nanterre had just been designated the seat of a new national unit for serial and unsolved crimes, the pôle des crimes sériels ou non élucidés, created by a law of December 22, 2021, and installed on March 1, 2022. Judge Khéris became its coordinating investigating judge. The investigation closed in February 2023, and on June 23, 2023, the investigating judge of the unit ordered Olivier to stand trial before the assize court of the Hauts-de-Seine for complicity in the abduction of Estelle Mouzin and in the abductions and murders of Marie-Angèle Domèce and Joanna Parrish, AFP and Belga reported. It was the unit's first case to reach trial.
The trial opened on November 28, 2023, with Judge Didier Safar presiding. More than 350 journalists were accredited. It was the first time Olivier faced a jury without Fourniret beside her. She was 75.
On the first day, after the presiding judge read out the facts, she said she regretted "everything that happened." Over hours of questioning she returned again and again to one theme. "He used me," she said. She told the court she had lived in fear during the marriage, for herself and for their son, though she said Fourniret had not hit her. She described him as cheerful and fun outside what she called "the thing." Asked what she had meant in her letters, she said she had no answer. Corinne Herrmann, for Domèce's siblings, said Olivier was speaking more freely than she had when Fourniret sat beside her in the dock. Didier Seban, for the Mouzin and Parrish families, said she was present when talking about her own suffering and "less there" when talking about the facts. Her lawyer, Richard Delgenes, told the court not to expect revelations. "Unlike him, she takes no particular pleasure in the pain of his victims or of the families," he said.
CBS News reported that during the first week she admitted "all the facts" in the case. Speaking of Joanna Parrish, she said: "It's because of me she's gone, it's unforgivable." Under cross-examination she described herself as never having been anything but the dog that had to obey its master. On many key questions, including where the bodies of Marie-Angèle Domèce and Estelle Mouzin are, she answered that she did not know or did not remember.
Joanna Parrish's father testified on December 4, 2023. He was 80. "Joanna's story ended in May 1990," he told the court, describing a bright and talented young woman whose life had been cut short. "There can be no greater tragedy than losing a child," he said. Olivier's son testified the week before the verdict and urged his mother to tell the court everything she knew. Investigators from the Versailles judicial police, heard on December 8, voiced doubts about Fourniret's involvement in Estelle's disappearance, AFP reported.
Prosecutors argued that Fourniret could not have killed so easily without her, and that she had gained the victims' trust knowing they would be killed. In their closing speech they asked for life imprisonment with a période de sûreté of 22 years. Before the jury withdrew, Olivier said: "I confirm what I said and I regret everything I did," and asked forgiveness of the victims and their families, "while knowing that it is unforgivable, everything I did."
On December 19, 2023, after more than ten hours of deliberation, the assize court of the Hauts-de-Seine answered yes to all twenty questions put to it. In the words of the Nanterre court, Olivier was sentenced to life imprisonment with a période de sûreté of 20 years "for complicity in the abductions and murders of Marie-Angèle Domèce and Joanna Parrish, and for the sequestration followed by death of Estelle Mouzin." The court also found her guilty of complicity in the attempted rape of Marie-Angèle Domèce and the rape of Joanna Parrish, AFP reported. News agencies summarized the verdict as complicity in three murders. "The sentence of life imprisonment is just, adequate, and in line with the extreme seriousness of the facts," Judge Safar said.
Olivier showed no reaction. Delgenes said she left with the same sentence she had arrived with, but with new guilty verdicts in three cases, and that her partial confessions had been taken into account without reducing her responsibility. Seban called the verdict "the end of a long fight for the families." Estelle's half-sister said: "There it is, justice has been given." Joanna Parrish's father said Olivier bore as much responsibility for the murders as Fourniret. Joanna's fiancé at the time called the verdict long-overdue recognition of her responsibility and the original police investigation "disjointed and unprofessional."
AFP reported that with the minimum terms of her sentences combined, she could not be considered for release before 2035. No appeal against the verdict was reported.
On May 6, 2024, in the civil phase of the case, Olivier was ordered to pay damages to Estelle's father, Eric Mouzin, the Paris court recorded.
Eric Mouzin sued the French State over the handling of his daughter's case, alleging gross fault and denial of justice. On September 3, 2025, the tribunal judiciaire of Paris ruled in his favor. The court found a faute lourde, a serious fault in the operation of the justice system: for nearly ten years the case file had not been kept coded and up to date, no regular summary reports had been written, ten successive investigating judges had handled the case, some for very short periods, and a lack of staff had hampered coordination with parallel investigations in other courts. It ordered the State to pay him 50,000 euros for moral harm and rejected his other claims.
Lydie Logé, 29, disappeared on December 18, 1993, in Saint-Christophe-le-Jajolet, in the Orne. Two earlier investigations, from 1994 to 1998 and from 2004 to 2009, ended without charges. The case was reopened in 2018 after DNA traces found in Fourniret's van were linked to her mother's DNA, The Brussels Times reported; Slate.fr dated the match to May 2019. Fourniret was charged in December 2020, months before his death.
Olivier has been under formal investigation (mise en examen) for complicity in Lydie Logé's disappearance since January 2021. In January 2025 the family's lawyer, Corinne Herrmann, said Olivier had admitted being present at the scene before the investigating judge of the Nanterre unit, "which is a form of confession for me." The family wanted her to give more details and help find Lydie's body, the lawyer said. By January 2025 the case had not come to trial, and Olivier is presumed innocent of any charge in it.
The question at the center of every trial was what kind of accomplice Olivier was. Her own account, given at Nanterre in 2023, was that Fourniret used her and that she obeyed him. Her lawyer stressed that she, unlike him, took no pleasure in the victims' pain. The prosecution, the families and the courts saw a woman who knew what would happen. Prosecutors at Nanterre said she won victims' trust knowing they would be killed. Joanna Parrish's father said she had actively encouraged and taken part in the crimes. In September 2026 RTBF, introducing a documentary on the case, described the long failures of the investigations in both countries and said that earlier action might have spared nearly ten girls.
Proven by the courts: Olivier's complicity in four murders, with other charges (2008); her conviction in the Farida Hammiche case (2018); her complicity in the abductions and murders of Marie-Angèle Domèce and Joanna Parrish, and her conviction in the case of Estelle Mouzin under the heading of sequestration followed by death (2023).
Not tried: Lydie Logé's disappearance, in which Fourniret was charged before his death and Olivier remains under investigation; she has not been convicted of any offence in that case.
Fourniret's own killings are his. He was convicted of seven murders in 2008 and of the Hammiche killing in 2018, and he confessed to the Domèce, Parrish and Mouzin killings, but he died before he could be tried for them. AFP reported in 2023 that he had confessed to 11 murders in all and that reports had suggested there could have been up to two dozen more. Francis Nachbar, the former prosecutor, has estimated 15 to 20 further victims, The Connexion reported. Those figures are estimates, not findings.
Details that vary in the reports: the number of crimes Olivier first described (six, eight, nine, ten or eleven, depending on the account); the number of murders in her 2008 conviction (four in most reports, five in one AFP report of 2018); Marie-Angèle Domèce's age (18 or 19); the year of the marriage (1989 in an AFP chronology, 1987 in Blick); and the date of Isabelle Laville's disappearance.
1987: Olivier answers a prisoner's advertisement in Le Pèlerin and begins writing to Michel Fourniret.
June 26, 1987: Fourniret is sentenced to five years in prison.
October 1987: Fourniret is released; the couple settle in the Yonne.
Late 1987: Isabelle Laville, 17, disappears.
1988: Their son is born; Farida Hammiche, 30, is killed.
July 8, 1988: Marie-Angèle Domèce disappears in the Yonne.
1989: Olivier and Fourniret marry (AFP chronology); Elisabeth Brichet, 12, is taken at Saint-Servais, Belgium.
May 1990: Joanna Parrish, 20, is killed in the Yonne.
December 18, 1993: Lydie Logé, 29, disappears in the Orne.
January 9, 2003: Estelle Mouzin, 9, disappears in Guermantes.
June 26, 2003: Fourniret is arrested in Belgium after a failed abduction.
2004 to 2005: Olivier describes a series of killings to investigators.
2005: Belgium hands Olivier over to France.
March 27, 2008: The trial opens at Charleville-Mézières.
May 28, 2008: Olivier is convicted of complicity in four murders, with other charges; life with a 28-year période de sûreté.
2010: The couple divorce.
2011 to 2012: The Domèce and Parrish files are closed, then reopened by Judge Sabine Khéris.
February 2018: Fourniret confesses to the Domèce and Parrish killings.
June 2018: Olivier confirms her earlier statements.
November 16, 2018: The Yvelines assize court sentences Olivier to 20 years in the Hammiche case.
November 21, 2019: Olivier tells Judge Khéris that she made the alibi call.
November 27, 2019: Fourniret is charged in the Mouzin case.
March 2020: Fourniret acknowledges involvement in the Mouzin case.
August 21, 2020: Olivier is charged as an accomplice in the Mouzin case.
December 22, 2020: Fourniret is charged in the Logé case.
January 2021: Olivier is placed under formal investigation in the Logé case.
May 10, 2021: Fourniret dies in Paris.
March 1, 2022: The Nanterre unit for serial and unsolved crimes is installed.
June 23, 2023: Olivier is ordered to stand trial at Nanterre.
November 28, 2023: The Nanterre trial opens.
December 19, 2023: Olivier is sentenced to life with a 20-year période de sûreté.
May 6, 2024: Civil damages are awarded against her to Eric Mouzin.
January 2025: The Logé family's lawyer says Olivier has admitted being present at the scene.
September 3, 2025: The Paris court finds the State at fault in the handling of the Mouzin investigation.