Sergio Méndez Arceo was an advocate of the Vatican II principles, which moved for changes in ritual distribution of the sacraments, deemphasis on saints, more studying of the bible, and sociological studies to aid ecclesiastical organization. Méndez Arceo attempted unsuccessfully to have the Mexican Conference of Bishops explore the violent suppression of the student movements in 1968, known as Mexico 68. As an individual without the support of the other bishops, Méndez Arceo assisted the imprisoned students, often called political prisoners, following the Tlatelolco Plaza massacre. In January 1970 he informed his fellow bishops of the condition of those prisoners; the bishops made no references to the massacre itself or the outcome, in keeping with its nonconfrontational stance toward the government at the time. Méndez Arceo was also involved in other social movements in Mexico such as striking Cuernavaca workers and guerrillas from Guerrero. The inaction by the episcopate, against what was viewed as rampant social repression, is believed to be what sparked many individual clergy and Jesuits, and the episcopate's social secretariat, to shift its emphasis from schools for the elite to social action programs.