By Michael Slicker
It is the birthday of murderess Marie LaFarge (1816), whose 1840 trial for poisoning her husband with arsenic became a cause célébre throughout France, with the public deeply divided over her innocence or guilt. She was the first person convicted by direct forensic evidence, and the case was one of the first followed closely by the public with daily newspaper reports. The trial was a spectacle attended by people from all over France. It included all the twists and turns of a good whodunit, including a celebrated expert witness and setbacks for both the prosecution and the defense. Marie LaFarge wrote her Mémoires(1841) while in prison. The novel The Lady and the Arsenic (1937) was based on the case as was the French film L’Affaire Lafarge (1938).