Despite Jules Bonnot and Octave Garnier exonerating him, he was accused and convicted of participating in the robbery of a Société Générale branch in Paris in 1912.

Journalists Albert Londres and Louis Roubaud [fr] secured his pardon and he returned to France where he spent the rest of his life as a furniture manufacturer.

Dieudonné denied the accusation, and a letter written by Octave Garnier while on the run exonerated him, but on 3 February 1913 the jury nonetheless found him guilty, and he was sentenced to death.

Raymond Callemin, convicted of the same crime, declared that he and Garnier were the only people culpable, which led to the President commuting Dieudonné's sentence to forced labour in perpetuity.

Back in France, there were campaigns for his release initiated by his wife, his lawyer, and journalists Albert Londres and Louis Roubaud [fr].