Historians seem to concur that his motivations were unclear. It has been suggested it was a response to the royal decree that Jansenists were to be refused communion at Mass. It may also be true that he had a grudge against the Jesuits, having been sacked as a domestic servant from one the college of Louis-le-Grand. His inability to keep down a job in other places too had probably led to the mental instability that he suffered. It seems clear however that he blamed the King for the ruling on the Jansenists not the Society of Jesus. This distinction didn’t matter to the enemies of the Jesuits and rumours where spread that it was the Jesuits that had ordered the killing.
The rumours failed to stick – but as all malicious gossip and libel does, it tainted the Jesuits in the minds of many and weakened their support. Historian William Banghert describes it as a loosened stone that would lead to the avalanche of attacks against the Society precipitated by the La Vallete affair later on. Certainly it deeply affected Louis XV and doubts started to enter his mind – which were to ruthlessy exploited by his mistress Madame de Pompadour. She had become an enemy of the Society after a Jesuit confessor had told her to leave the court and reform her life.