Until 1950, this prison colony was known as a feared detention center, due to violence, disease, and forced labor.

Among the most dangerous to escape were criminals sentenced for drug trafficking, 28 murderers, and kidnappers.

Another group of settlers is made up of religious ministers and acolytes of the Catholic Church, nuns of the Order of Social Service, and invited teachers, technicians and their relatives.

The colony is governed by a state official who is both the governor of the islands and chief judge.

The first chaplain in Islas Marías history was prisoner Arturo Salcido, who was sentenced for trafficking of drugs.