On May 11, 1949, the body of Léon Besnard was dug up in the cemetery at Loudun, in the Vienne, and his organs were packed into jars of the kind used for preserving peas and green beans and sent to Marseille for analysis. The record says ten jars were sent. The expert, Dr. Georges Béroud, received eleven, and analyzed nine. His report found arsenic, fifteen milligrams to the kilogram, and on July 21, 1949, Léon's widow, Marie Besnard, was charged with poisoning him. It was the start of the longest criminal affair of postwar France, and of one of its most celebrated collapses of forensic evidence.
The case had begun with talk. Léon Besnard had died in October 1947, and a friend of the couple, Louise Pintou, told people that he had said on his deathbed that his wife was poisoning him. The rumor reached the gendarmerie and the investigating magistrate, a judge named Roger who was twenty-five and saw the first big case of his career. Once arsenic was reported in Léon, the exhumations spread to the people around her who had died. By the time she came to trial, the prosecution counted twelve.
She had been born Marie Joséphine Philippine Davaillaud on August 15, 1896, at the hamlet of Les Liboureaux in Saint-Pierre-de-Maillé, the daughter of a farmer. In 1920 she married her cousin, Auguste Antigny, who had tuberculosis and died of pleurisy on July 21, 1927; exhumed, his remains were reported to hold sixty milligrams of arsenic. In 1928 she married Léon Besnard, and the couple took his parents into their house when they came into family money; his father died, apparently after eating bad mushrooms, and his mother three months later, of what was taken for pneumonia. Her own father and mother died, and so did elderly relatives and neighbors, and she inherited, directly or indirectly, from nearly all of them. She and Léon owned a prosperous rope works. The magistrate found motives in the inheritances and in a rumored affair with Alfred Dietz, a former German prisoner of war who worked for the family. The town called her la bonne dame de Loudun, the good lady of Loudun.
The first trial opened at Poitiers in 1952 and fell apart over the science. Her lawyers, among them Albert Gautrat, Jacqueline Favreau-Colombier and Frédéric Hayot, showed that the jars had been mislabeled, that some might have been lost or substituted, and that Béroud, cross-examined, could not defend his own work. The court ordered new expert reports. A second trial, at Bordeaux in 1954, went no better for the prosecution; a panel of senior experts including Frédéric Joliot-Curie and René Truhaut was appointed, and she was released on bail of 1.2 million francs, which, with her property seized, she could not easily raise. The singer Charles Trenet offered to pay it.
The defense's investigation of the cemetery showed that the soil at Loudun could itself be saturated with arsenic, from the sulfate sprayed on flowers and the zinc of funeral ornaments, and that arsenic taken up from the ground after burial could not be told apart, by the methods used, from arsenic swallowed before death. Newer analysis by neutron activation was reported to have found none in the skeletons. At the third trial, before the assize court of the Gironde at Bordeaux from November 20 to December 12, 1961, the prosecution largely abandoned the scientific file and argued from her character instead. On December 12, 1961, twelve years after she was charged, she was acquitted for lack of proof.
She had lost most of her property and never received compensation from the state or from her accusers. She went back to Loudun, wrote her memoirs, and died there on February 14, 1980, at eighty-three; one account gives 1981. She left her body to science, so she has no grave in the cemetery where the case began. Whether any of the twelve was murdered has never been established.