 Under pressure from some Mexican leaders, and personally feeling that the death penalty was an unjust punishment for some defendants, Scott spared 20, but the rest were executed.In early September, negotiations between Trist and the Mexican government broke down, and Scott exercised his right to end the truce.In the subsequent Battle for Mexico City, Scott launched an attack from the west of the city, capturing the key fortress of Chapultepec on September 13.