He was born in Santiago on December 21, 1941. He studied law at the University of Chile, sworn in as a lawyer in 1967. After the 1973 coup, he joined the Pro-Peace Committee to take on the defense of the persecuted against the Councils of War. He was part of the Vicaría de la Solidaridad, where he was head of the Judicial Area. Together with a remarkable team, he fulfilled one of the most relevant roles in protecting people persecuted by the regime by developing a tireless work of gathering background information and filing appeals for each detained, disappeared person and political prisoners held by the dictatorship.
He actively participated in preparing documents and reports for international organizations, such as the United Nations, reporting on human rights violations in the country. In such denouncement work, he was required by the military justice for “offenses against the armed forces”, even being charged as “convict” in addition to facing threats, both to himself and to members of his family, who demanded that he stop his actions in defense of human rights.
He was summoned due to his vast experience to form part of the so-called “Dialogue Table” – an institution created in August 1999 by the government of Eduardo Frei Ruiz-Tagle, to advance in the search for the victims of forced disappearance of the civic-military dictatorship. Garretón was also Special Rapporteur of the United Nations, fulfilling several functions in that body, along with an active role in legal actions surrounding the extradition process of Augusto Pinochet.
Between 2010 and 2016, he was part of the first Board of Directors of the INDH. In 2020, this same collegiate body, recognizing his extensive career in the defense and promotion of human rights, awarded him the National Human Rights Award on August 14, 2020, in a virtual ceremony resulting from the Coronavirus pandemic.
On that occasion, Roberto Garretón pointed out regarding his career during the civic-military dictatorship: “I worked as a labor lawyer. But that event had such an impact on my personal and professional life that it made me look at law from a different perspective, assuming the vision of a Spanish philosopher as my own: law is useful for life, or it is useless. In addition, he recalled the human rights violations that occurred as of October 18, 2019, and the need to find truth, justice, and reparation for the victims.