 From 1962 to 1965 he attended the Second Vatican Council, during the course of which he was one of the cardinal electors who participated in the 1963 papal conclave that selected Pope Paul VI.Pope Paul had Cardinal Roberti ask the prefects of the Roman congregations to suggest possible reforms within the Curia.Before resigning as prefect of the Apostolic Signatura on 24 March 1969, Roberti exercised his right as a Cardinal-Deacon of ten years' standing to become a Cardinal Priest, receiving the title of Ss.