He was a member of the Democratic Action group, in turn part of the Democratic Party opposed to the Christian socialist government of Rafael Ángel Calderón Guardia who was allied to the Costa Rican Communist Party and led the revolution against Calderón after the elections in 1948 were canceled by the Constitutional Congress when Calderón was defeated by the opposition candidate (and future ally of Calderón) Otilio Ulate arguing electoral irregularities, being commander of the so-called National Liberation Army that emerged victorious in the war of 48.