He became a chaplain of the Buenos Aires Province Police in the 1970s. The force was commanded by General Ramón Camps. This was during the military dictatorship known as National Reorganization Process ("El proceso") (1976–1983), when the military and security forces took extreme actions to suppress political dissent in the country. The period became known as the Dirty War, and the government was later held responsible for tens of thousands of forced disappearances, kidnappings, torture, and deaths of political prisoners, in addition to widespread attacks of rural insurgents, which was later assessed as genocide. Going beyond acting as a spiritual adviser to police and suspects, Wernich worked with the rank of Inspector in Miguel Etchecolatz's Direction of Investigations of the provincial police.