Marie Besnard was arrested in July 1949, released from prison in April 1954 and acquitted by a jury at Bordeaux in December 1961. She had been charged in July 1949 with poisoning her second husband, Léon Besnard, a rope merchant in the small town of Loudun, in the Vienne department of western France. As more bodies in her family were exhumed and analysed, the charge grew to twelve deaths, among them both of her husbands, her parents and her parents-in-law. The case rested on arsenic: on what a Marseille laboratory reported finding, and on whether that arsenic had been swallowed in life or had come from the ground after burial.
Three trials followed: at Poitiers in 1952, and twice at Bordeaux, in 1954 and 1961. Each time the scientific evidence came under attack, and each time the court asked for more of it. In the end the jury answered no to the question of her guilt in every one of the deaths, and she was acquitted. She returned to Loudun and died there in 1980.
The case became one of the best known in French legal history. Two toxicologists who re-examined it in 2006, Jean-Pierre Anger and Jean-Pierre Goullé, called it a quarrel of experts that ended in an acquittal. Three scientists writing in L'Actualité Chimique in 2003 drew a sharper conclusion: that the presence of arsenic in a body or in hair does not by itself prove poisoning, and that rumour rather than evidence had driven the prosecution.
She was born Marie Joséphine Philippine Davaillaud on August 15, 1896, on a farm at Saint-Pierre-de-Maillé, a village in the Vienne. Her parents, Pierre Davaillaud and Marie-Louise, born Antigny, were farmers who, according to Anger and Goullé, valued education. She went to a convent school and then to the public school, but typhoid fever at the age of 12 ended her schooling before she could sit for her certificate.
On April 6, 1920, at 24, she married her cousin Auguste Antigny. About four years into the marriage he fell ill with pleurisy. He recovered and took a post as caretaker and gardener at a nearby château, but late in 1926 he began coughing blood, and he died on July 1, 1927. She was a widow at 31.
Through letters with a cousin in Loudun, she came to know Léon Besnard, a rope merchant then 35. She had gone back to the family farm after Auguste's death, and in January 1929 Léon wrote to her. He proposed twice. They married at Saint-Pierre-de-Maillé on August 12, 1929, spent a four-day honeymoon in the Basque country, and settled in Loudun, a town of about 5,000 people. Anger and Goullé describe it as a place where gossip travelled fast.
The couple were together for 18 years. At the start of the Second World War a series of deaths struck their families, and in 1941 they moved into the house of Léon's parents. Marie's mother and a friend of the couple, Blanche Rivet, lived with them. After the war they took in a young German prisoner of war whom the household called Ady. Local gossip made him Marie's lover, and she was also labelled a collaborator.
Between 1927 and 1949, twelve people close to Marie Besnard died, besides Léon. The list that later came into the hands of investigators, as Anger and Goullé set it out, ran as follows, with the year of death and age:
her first husband, Auguste Antigny, 1927, aged 33;
a great-aunt, 1938, aged 86;
a friend of the Besnard couple, 1939, aged 64;
her father, 1940, aged 78;
the grandmother of her second husband, 1940, aged 92;
her father-in-law, 1940, aged 78;
her mother-in-law, January 1941, aged 68;
a sister-in-law, March 1941, aged 45;
the widow of the couple's friend, Blanche Rivet, December 1941, aged 49;
a cousin of her second husband, July 1945, aged 88;
that cousin's sister, also in July 1945, aged 83;
her mother, January 14, 1949, aged 71.
The man who drew up the list noted beside each one that it had brought Marie Besnard a bequest or an inheritance, and inheritance became the motive the prosecution put forward, together with the rumoured affair.
In the winter of 1946 Léon Besnard had a severe bout of influenza and spent three months in bed. In the autumn of 1947 the couple spent a few days at the family farm at Saint-Pierre-de-Maillé. On October 16, before they drove back to Loudun, Marie served lunch: soup, fried eggs, beans, meat, wine and coffee. Afterward Léon pumped up the car tyres and was sick. He drove the family home, tidied up and felt ill again before dinner. He went to bed and woke with the same symptoms. Marie, too, felt unwell.
The family doctor diagnosed a liver attack and prescribed a diet. Léon's symptoms continued, and a second doctor ordered a blood test, which showed a moderately raised level of urea. Léon Besnard died on October 25, 1947, nine days after the meal. The 2003 article in L'Actualité Chimique, by Georges Meyer, Pierre Chevallier and Ivan Ricordel, states that he was reported to have died of uremia, a failure of the kidneys, not of poison.
A few days before All Saints' Day, the local postmistress, Louise Pintou, told two brothers named Massip that Léon had confided to her that his wife was poisoning him. Auguste Massip looked up arsenic in a medical dictionary, asked her whether the symptoms matched, and on November 4, 1947, wrote to the public prosecutor at Poitiers. His letter became a central document in the file.
The gendarmerie made discreet inquiries and closed the matter. But talk spread through Loudun, and townspeople began to treat the widow with suspicion.
On October 17, 1948, a fire destroyed the Massip family's château at Montpensier. Auguste Massip blamed Marie Besnard and called it revenge for his letter. Within days, two children of the household's domestic staff were found to have started it while playing with matches among dried bean plants. On January 14, 1949, Marie's mother died of influenza. Massip, still convinced, drew up his list of twelve deaths and worked with the investigators: Commissioner Nocquet and Inspector Normand of the judicial police, whom Anger and Goullé describe as young and ambitious, and the investigating magistrate at Loudun, Pierre Roger. After a suspicious break-in at Louise Pintou's home, she repeated under questioning what she said Léon had told her before he died.
On May 11, 1949, on the prosecutor's order, Léon Besnard's body was exhumed at Loudun. (Meyer and his co-authors date the order May 10.) The body was analysed by Dr. Georges Béroud, of the police scientific laboratory at Marseille, a sworn expert of the appeal court at Aix-en-Provence.
At 9 a.m. on July 21, 1949, Marie Besnard was arrested at her home in Loudun and taken to the police station at Poitiers for further questioning. She said again and again that no one had poisoned her husband. She was then told what Béroud had reported: using the Marsh and Cribier methods, the standard tests for arsenic of the day, he had found an amount of arsenic in Léon's body that he judged well above normal, and he concluded that the arsenic had been absorbed before death and that poisoning was plausible. She disputed the result. A warrant was issued, she was charged with poisoning her husband, and that evening she entered the prison at Poitiers.
On the advice of a Loudun lawyer, she chose two defence counsel: Henri Cluzeau of the Poitiers bar and René Hayot of the Paris bar. On August 1, 1949, they asked for a second, independent expert examination. It was refused.
Meanwhile the twelve people on Massip's list were exhumed, and analysed at Béroud's laboratory in Marseille. On October 31, 1949, he reported arsenic in eleven of the twelve bodies. He reported none in the cemetery soil. On the strength of that report she was charged with eleven further deaths. Meyer and his co-authors give the total number of bodies exhumed by the police as 13, counting Léon.
Later hearings would show errors in the identification and handling of the material he analysed.
From the day of her arrest until the eve of her first trial in February 1952, Marie Besnard underwent psychiatric examinations. One of the experts described her as "anormalement normale", abnormally normal, and found her responsible for her actions.
Her defence grew. Albert Gautrat and Jacqueline Favreau-Colombier joined Cluzeau and Hayot, and the defence enlisted its own scientific advisers: Perperot, a chemist attached to the Paris appeal court, and Georges Schuster, a member of the Académie de Pharmacie. Both would testify. From the beginning Gautrat pressed one argument above all: that a sound analysis had to measure the arsenic in the soil around each grave. If arsenic in the ground could not reach a body, he asked, why test the soil at all? Meyer and his co-authors note that the question would later matter a great deal.
The first trial opened on February 20, 1952, before the assize court of the Vienne at Poitiers, 30 months after her arrest. She was accused of causing the deaths of eleven relatives and a friend; the motives alleged were inheritance and an adulterous affair. The presiding judge, Edgar Favard, questioned her over several days, and her whole past was gone over in court. The prosecution called about 80 witnesses.
On the fourth day Béroud took the stand. The court raised problems with the handling and transport of the material he had analysed, and he could not answer them. Asked about his methods, he gave confused replies. Then came the moment that defined the case. Béroud had stated that he could not mistake arsenic for antimony; in the Marsh test, the two elements leave similar deposits on glass. Gautrat produced six test tubes prepared the night before by Dr. Roger Lebreton, each containing an antimony deposit. Accounts of what followed differ in detail. Anger and Goullé write that Béroud said three of the six contained arsenic; Meyer and his co-authors write that he hesitated and handed two to the court usher as arsenic. In both accounts none of the tubes held arsenic, and the expert's standing was badly damaged.
The next day Béroud was absent, citing illness. His colleague Aimé Médaille took his place, and his answers satisfied no one. Inconsistencies in Béroud's work came to light, including labelling errors and contradictions between his reports. On February 24 the defence's experts told the court the analyses lacked rigour. Béroud returned, supported by two gendarmes, and refused to debate with Schuster. Perperot testified that he had found arsenic in the soil of the Loudun cemetery, contrary to Béroud's results. He also pointed out that one report attributed a death to lead arsenate, yet no one had tested for lead.
The defence asked for a new expert examination, so that the court could rule on sounder reports, and the court agreed. There was no verdict. Meyer and his co-authors write that Béroud's career as an expert ended at Poitiers. Marie Besnard went back to prison.
On March 22 and 23, 1952, the bodies were exhumed a second time. Three Paris professors were appointed: Émile Kohn-Abrest, René Fabre and Henri Griffon, head of the laboratory of the Paris police prefecture. The forensic doctor René Piedelièvre took part, and the material was analysed in Paris. Besides the old Marsh and Cribier tests, they used a new technique, neutron activation, a nuclear method that Griffon had pioneered for arsenic in 1951. Meyer and his co-authors write that the exhumation was carried out in chaotic conditions. The experts' report, delivered after about a year, found arsenic in the cemetery soil, contradicting Béroud.
The questions the case now turned on were scientific ones that the earlier inquiry had not addressed. Was the arsenic in the Loudun soil soluble? Could it pass from the soil into a body after burial? Could rainwater carry arsenic from one grave to another?
In 1953 the case was transferred from Poitiers to the assize court at Bordeaux, on grounds of public order, and Marie Besnard was moved to Bordeaux with it.
The second trial ran from March 15 to April 1, 1954, at Bordeaux, with Henri Pourquery de Boisserin presiding. The advocate general told the court that only six of the eleven deaths remained in question: for the others, prosecution was barred by time or the arsenic levels were too low. Louise Pintou and the Massip brothers testified again.
From March 24 the experts took the stand. Fabre, Kohn-Abrest and Griffon reported large amounts of arsenic. Under questioning Fabre admitted that he did not know whether arsenic dissolves in a decomposing medium. Kohn-Abrest held that the arsenic had been absorbed before death, but his figures for Marie Besnard's mother implied she had swallowed a quantity of poison that Anger and Goullé describe as implausible. The defence attacked Griffon's figures, arguing that uncertainties had accumulated through his methods of calculation. A report by the physicist Frédéric Joliot-Curie also supported the finding of high arsenic levels. Piedelièvre confirmed the 1952 results, though in more qualified terms than Béroud had used.
The defence's own experts, chosen by René Hayot, appeared as witnesses. Griffon, Meyer and his co-authors write, refused to discuss his results with them. Marcel Le Peintre argued that groundwater dissolves arsenic from rock, and that the water in the cemetery contained arsenic. Dr. Ollivier argued that microbes in the soil can turn insoluble arsenic into a soluble form. Professor Keilling pointed out that zinc, common in cemeteries, contains arsenic that microbes can release. The court then heard that the cemetery gardener grew potatoes and cereals and used calcium arsenate against Colorado beetles; the defence added that nearby land grew potatoes and chrysanthemums, and that arsenate pesticides were in use.
The last of the defence scientists was Louis Truffert, who taught toxicological chemistry at the Paris Faculty of Medicine. He told the court that arsenic is soluble, that runoff can carry it through soil, and that it binds to hair and resists even strong washing. His evidence shook the court experts' certainty.
On April 1, 1954, the court rejected the claims of the civil parties and ordered a further expert review. It asked the new experts a single question: whether, in the current state of science, it was possible to conclude that there had been arsenic poisoning before death. On April 12, 1954, Marie Besnard was granted provisional release. She returned to Loudun on May 12.
The new panel was formed, with difficulty, in 1955: Maurice Lemoigne of the Académie des Sciences, a specialist in soil chemistry; René Truhaut of the Paris Faculty of Pharmacy, a toxicologist; and Frédéric Joliot-Curie, chosen, Meyer and his co-authors write, for his reputation. After the 1954 trial Joliot-Curie had asked his chemist Pierre Süe to develop a neutron activation method specific to arsenic, which a Dr. Michon presented at a meeting at Saclay in 1955. It was far more sensitive than the older chemical tests, about 10,000 times more so than the Cribier method by their account, and was probably used only on a single sample said to come from Léon Besnard, whose origin, they note, remained unclear.
Joliot-Curie's health failed, and he died in August 1958 before he could give evidence. His deputy at the Collège de France laboratory, the physicist Pierre Savel, took his place. In the view of Meyer and his co-authors, neither man had the time or the appetite for the dispute.
Gautrat had been asking since 1954 for Griffon's laboratory notebooks. They reached the file only on February 16, 1961. They turned out to be working notes and drafts, full of crossings-out, with figures that differed from the final reports and some pages destroyed. Griffon was criticised for failing to follow the standards he himself taught.
The third trial opened before the assize court at Bordeaux on November 20, 1961. The charges were the same as in 1952, and Marie Besnard again declared her innocence. She was questioned about the deaths of eleven people in her circle.
The scientific debate began on the third day. Gautrat challenged Lemoigne on the precision of his controls, Truhaut on his methods of analysis, and Griffon on his neutron activation work. The experts' measurements of arsenic in the soil differed from one another. Zinc and runoff were raised again as possible sources. Errors in quantities and misplaced decimal points confused the jurors, and the state of Griffon's notebooks was put before the court. Meyer and his co-authors write that the experts concluded that six of the 13 bodies contained traces of arsenic; Kohn-Abrest kept to the Marsh method, while Griffon argued that the Cribier method was the more sensitive.
Truffert again rejected the court experts' reading. In his view the arsenic had come from outside the bodies, carried in by water from the surrounding soil, and Ollivier and Keilling supported him. He described his experiments on the binding of arsenic to hair and offered to repeat them in public. Gautrat told the jury that the whole case against Marie Besnard rested "sur un mensonge et sur une erreur": on a lie and on a mistake.
Anger and Goullé write that as the days passed, the official expert evidence on which the prosecution had relied fell apart, and that nothing remained for the prosecution but the gossip of Loudun. After the speeches of the civil party, the prosecutor general and the defence, the jury retired.
The jury answered no to the question of Marie Besnard's guilt in the deaths of each of the eleven people, and she was acquitted. Meyer and his co-authors date the verdict December 13, 1961, and give the third trial as running from November 20 to December 12; in their words, every count of the accusation against her was rejected. Writing in Slate, the journalist Philippe Boggio described the acquittal as one for lack of evidence.
At the end of three trials, two rounds of exhumations and a long series of expert reports, no court found that any of the deaths in her family was a crime.
Marie Besnard went home to Loudun. She lived there until her death in 1980, and she left her body to the Faculty of Medicine, according to Meyer and his co-authors.
Anger and Goullé, both toxicologists who had worked as court experts, returned to the case in the Annales de Toxicologie Analytique in 2006. On the narrow question the toxicologists had been asked, they wrote, the experts largely agreed: eleven of the twelve bodies held more arsenic than normal, and more than control bodies from the same cemetery. But the experts were then asked to judge environmental questions, how arsenic moves through soil and whether it dissolves in water, on which they had little expertise. The defence drew them onto that ground and exposed them there.
The two authors criticised the court experts for paying too little attention to how samples were collected, for leaving analyses to assistants instead of doing the work themselves, and for not submitting their interpretations to other experts. They called the trials a dialogue of the deaf: the prosecution trusted the court's experts, while the defence challenged every result. They quoted René Hayot's advice to confront expert opinion directly and never to leave experts to argue only among themselves. Their own conclusion was a lesson for their profession: an expert is not a professional of truth but of knowledge, whose task is to say what is possibly true and what is certainly false.
Meyer, Chevallier and Ricordel, writing in 2003, set the case beside the trial of Marie Lafarge at Tulle in 1840, another arsenic case in which a famous expert's results were disputed. In their view the Besnard affair showed that arsenic found in tissue or hair is not in itself proof of poisoning. They argued that rumour, not evidence, had driven the prosecution, and that the scientific disputes had been used to support a verdict decided in advance. It was the accused woman, they wrote, who paid the heaviest price.
The verdict did not settle opinion. Boggio, writing in Slate, called her the famous Marie Besnard, acquitted but still suspected of having killed twelve people, and wrote that many magistrates and criminologists regarded her as the most talented of the "black widows". He suggested that her open display of virtue, far from the image of a poisoner, had won over the jurors in one of the longest trials in French court history.
In 2024 the historian Marc Lefrançois, author of a history of women criminals published in 2023, told Actu-Juridique that the case had been a battle of experts, and that she was acquitted because of errors, imprecision and blunders. He added that he was personally convinced she was guilty. That is his opinion, not a finding of any court. The courts' only finding was the jury's answer at Bordeaux.
Proven by a court: nothing against her. The jury at Bordeaux answered no on her guilt in each of the eleven deaths put to it, and she was acquitted in December 1961.
Alleged and not proven: that Léon Besnard and the eleven others died of arsenic poisoning, and that she gave it to them. The prosecution's case rested on the reports of Béroud (1949) and of Kohn-Abrest, Fabre and Griffon (1952 to 1954), and on the motive of inheritance. The defence's experts argued that arsenic from the cemetery soil, water, zinc and agricultural pesticides could account for the readings. By 1954 the prosecution itself treated only six deaths as still in question, and in 1961 the experts reported traces of arsenic in six of the 13 bodies, according to Meyer and his co-authors.
Accounts differ on several points: the date the first exhumation was ordered (May 10 or May 11, 1949); the number of bodies exhumed (twelve besides Léon, or 13 in all); what happened with the test tubes at Poitiers (Béroud named three of six, or handed over two, as arsenic); and the date of the verdict (the trial is given as ending on December 12, and the verdict as December 13, 1961). The cause of Léon Besnard's death was given by his doctors as a liver complaint and is reported by Meyer and his co-authors as uremia.
The rumours: that Léon told Louise Pintou on his deathbed that his wife was poisoning him, and that Marie Besnard had an affair with the German prisoner who lived with the family. Both were reported as gossip and as testimony; neither was proven.
August 15, 1896: Marie Joséphine Philippine Davaillaud is born at Saint-Pierre-de-Maillé (Vienne).
April 6, 1920: marries her cousin Auguste Antigny.
July 1, 1927: Auguste Antigny dies.
August 12, 1929: marries Léon Besnard, a rope merchant, at Saint-Pierre-de-Maillé; the couple settle in Loudun.
1938 to 1945: further relatives and friends die, among them her father (1940) and her parents-in-law (1940 and 1941).
1941: the couple move into the house of Léon's parents.
October 16, 1947: Léon falls ill after a meal at the family farm.
October 25, 1947: Léon Besnard dies.
November 4, 1947: Auguste Massip writes to the public prosecutor at Poitiers; a gendarmerie inquiry closes the matter.
October 17, 1948: fire at the Massip château at Montpensier; two children are found responsible.
January 14, 1949: Marie's mother dies.
May 11, 1949: Léon Besnard's body is exhumed.
July 21, 1949: Marie Besnard is arrested, charged with poisoning her husband and jailed at Poitiers.
August 1, 1949: the defence's request for a second expert examination is refused.
October 31, 1949: Béroud reports arsenic in eleven of twelve further bodies; eleven more deaths are added to the charge.
February 20, 1952: first trial opens at Poitiers; Béroud is discredited and new expert reports are ordered.
March 22 and 23, 1952: second exhumations.
1953: the case is transferred to Bordeaux.
March 15 to April 1, 1954: second trial at Bordeaux; new expert review ordered.
April 12, 1954: provisional release; she returns to Loudun on May 12.
1955: Lemoigne, Truhaut and Joliot-Curie appointed.
August 1958: Joliot-Curie dies; Pierre Savel replaces him.
February 16, 1961: Griffon's notebooks are filed.
November 20, 1961: third trial opens at Bordeaux.
December 1961: the jury answers no on her guilt in each death; she is acquitted.
1980: Marie Besnard dies in Loudun.