The body of Leon Besnard is exhumed in Loudun, France, by authorities searching for evidence of poison. For years, local residents had been suspicious of his wife Marie, as they watched nearly her entire family die untimely and mysterious deaths. Law enforcement officials finally began investigating Marie after the death of her mother earlier in the year.
Marie married Leon in August 1929. The couple resented the fact that they lived relatively modestly while their families were so well off. When two of Leon's great aunts perished unexpectedly, most of their money was left to Leon's parents. Consequently, the Besnards invited Leon's parents to live with them.
Shortly after moving in, Leon's father died, ostensibly from eating a bad mushroom. Three months later, his widow also died and neighbors began chatting about a Besnard family jinx. The inheritance was split between Leon and his sister, Lucie. Not so surprisingly, the newly rich Lucie died shortly thereafter, supposedly taking her own life.
Becoming increasingly greedy, the Besnards began looking outside the family for their next victim. They took in the Rivets as boarders, who, under the Besnards' care, also died abruptly. No one was too surprised when the Rivets' will indicated Marie as the sole beneficiary.
Pauline and Virginie Lallerone, cousins of the Besnards, were next in line. When Pauline died, Marie explained that she had mistakenly eaten a bowl of lye. Apparently, her sister Virginie didn't learn her lesson about carelessness, because when she died a week later, Marie told everyone that she too had inadvertently eaten lye.
When Marie fell in love with another man in 1947, Leon fell victim to her poisoning as well. Traces of arsenic were found in his exhumed body, as well as in the rest of her family's corpses. But Marie didn't let a little bit of pesky evidence get in her way. She managed to get a mistrial twice after trace evidence was lost while conducting the tests for poison each time. By her third trial, there wasn't much physical evidence left. On December 12, 1961, Marie Besnard was acquitted. The "Queen of Poisoners," as the French called her, ended up getting away with 13 murders.
Taken from: http://www.history.com/this-day-in-history [04.05.12]