Armenta, editor of the Guasave-based weekly El Regional in Sinaloa, was beaten to death by the lawyer Felipe de Jesús Lizárraga. His body was dumped in a canal near Guasave. Lizárraga, who was an acquaintance of Armenta and was driving with him in the car that was found at the scene, originally claimed that police agents attacked them. But because of contradictions in his statement and other circumstantial evidence, the lawyer was charged with the murder and detained.
Soon after, however, Lizárraga, then the president of the Lawyer's Guild of Sinaloa, was freed, setting off demonstrations by local journalists, who believe he killed Armenta after a fight about articles the journalist had written about him. As a result of the demonstrations, Lizárraga was rearrested and put on trial. On November 18, he was convicted and sentenced to 13 years and three months in prison and fined 11,000 nuevos pesos ($1,200) Lizárraga appealed the sentence.