52 There are occasions, doubtless, when it is fitting that the law should intervene to prevent certain associations, as when men join together for purposes which are evidently bad, unlawful, or dangerous to the State. In such cases, public authority may justly forbid the formation of such associations, and may dissolve them if they already exist. But every precaution should be taken not to violate the rights of individuals and not to impose unreasonable regulations under pretense of public benefit. For laws only bind when they are in accordance with right reason, and, hence, with the eternal law of God.(38)
Source: Rerum Novarum (Vatican.va)