This crime was widely discussed at the time, and the interwar period generated multiple speculations, involving the secret services and the violent political group La Cagoule.
Police investigations, led by Commissioner Badin found that the victim was leading a double life, and that her entire family, originally from Italy, had relocated to France.
Many Italians came to Paris at the time in search of work.
Toureaux worked during the day in a factory, but was found to also be working under a false name as an attendant at a dance hall with a seedy reputation, and frequently making discreet visits to the Italian Embassy.
She was known to have had various lovers, leading police to initially suspect a crime of passion.
However, further investigation revealed she had been working as a spy.
She had been employed to infiltrate La Cagoule, a far-right terrorist group that was often overlooked later in post-war France.The case was dropped two years later at the outbreak of the Second World War.