The Church, the "pillar and bulwark of the truth," "has received this solemn command of Christ from the apostles to announce the saving truth." "To the Church belongs the right always and everywhere to announce moral principles, including those pertaining to the social order, and to make judgments on any human affairs to the extent that they are required by the fundamental rights of the human person or the salvation of souls."
Source: Catechism of the Catholic Church (Vatican.va)