The conspirators were hanged for 'high treason'.
He is guilty of 'treason'.
(..) and a new era was born. The freedom has a cost. And the traitors was defeated. Peace-War as a nation. We would never know this treason again. And so, it was decreed... That each year. The various districts of Panem would offer up in tribute... One young man and woman. (..)2012 The Hunger Games