The conspirators were hanged for 'high treason'.
He is guilty of 'treason'.
(..) - Say the lord's prayer. Our father... ...who art in heaven ... I can't ... Shut up. Shut up! From here on you are a prisoner charged with treason. Take him to the cage. Take him to the cage! You handle or I'll shoot him! I thought he was gonna die. - Get up. - Doc. (..)2015 The Revenant