On August 9, 1765, the wooden crucifix on a bridge in Abbeville was vandalized. Catholicism was then the state religion of France and the religion of the vast majority of the French public. The bishop of Amiens roused the furor of the faithful and asked churchgoers to reveal all they could about the case to the civilian judges, under pain of excommunication. Nobody actually revealed anything about the vandalizing itself, but some accused three young men, Gaillard d'Etallonde, Jean-François de La Barre and Moisnel, of not having removed their hats when a procession had passed. La Barre's bedroom was searched and three prohibited books, including Voltaire's Philosophical Dictionary, were found.

La Barre was tortured into confessing his alleged crimes. He was then sentenced by the Paris parlement (high court) to be tortured again, beheaded, then have his body thrown into the flames along with his copy of the Philosophical Dictionary. Voltaire attempted to have his conviction reversed, to no avail. It was reversed by the National Convention during the French Revolution in 1794.