There is both positive and negative criteria that bishops and other authorities consider with the help of this document. First, the document offers some notes to put it all into context.
Preliminary Note: Origin and character of these norms.
At the time of the Annual Plenary Congregation during November 1974, the Fathers of this Sacred Congregation studied the problems relating to apparitions and supposed revelations, and the consequences which often result from these, and they arrived at the following conclusions:
1. Today more than formerly, the news of these apparitions is spread more quickly among the faithful thanks to the means of information ("mass media"); in addition, the ease of travel supports more frequent pilgrimages. Also, the ecclesiastical authority was itself brought to reconsider this subject.
2. Similarly, because of current instruments of knowledge, the contributions of science, and the requirement of a rigorous criticism, it is more difficult, if not impossible, to arrive as speedily as previously at judgements which conclude, as formerly happened, investigations into this matter (“constate de supernaturalitate, non constat de supernaturalitate”); and because of that, it is more difficult for the Ordinary to authorize or prohibit public worship or any other form of devotion of the faithful.
For these reasons, so that the devotion stirred up among the faithful by facts of this kind can appear as a disposition in full communion with the Church, and bear fruit, and so that the Church itself is able to ultimately distinguish the true nature of the facts, the Fathers consider that it is necessary to promote the following practice in regard to this matter.
So that the ecclesiastical authority is able to acquire more certainty on such or such an apparition or revelation, it will proceed in the following way:
a) Initially, to judge the facts according to positive and negative criteria (cf. below, n.1).
b) Then, if this examination appears favorable, to allow certain public demonstrations of cult and devotion, while continuing to investigate the facts with extreme prudence (which is equivalent to the formula: “for the moment, nothing is opposed to it”).
c) Finally, after a certain time, and in the light of experience, (starting from a particular study of the spiritual fruits generated by the new devotion), to give a judgement on the authenticity of the supernatural character, if the case requires this.
I. Criteria of judgement, concerning the probability at least, of the character of the apparitions and supposed revelations.
A) Positive criteria:
a) Moral certainty, or at least great probability, as to the existence of the fact, [revelation] acquired at the end of a serious investigation.
b) Particular circumstances relating to the existence and the nature of the fact:
1. Personal qualities of the subject—in particular mental balance, honesty and rectitude of moral life, habitual sincerity and docility towards ecclesiastical authority, ability to return to the normal manner of a life of faith, etc.
2. With regard to the revelations, their conformity with theological doctrines and their spiritual veracity, their exemption from all error.
3. A healthy devotion and spiritual fruits which endure (in particular, the spirit of prayer, conversions, signs of charity, etc).
B) Negative criteria:
a) A glaring error as to the facts.
b) Doctrinal errors that one would attribute to God himself, or to the Blessed Virgin Mary, or the Holy Spirit in their manifestations (taking into account, however, the possibility that the subject may add something by their own activity—even if this is done unconsciously—of some purely human elements to an authentic supernatural revelation, these having nevertheless to remain free from any error in the natural order. Cf. St Ignatius, Spiritual Exercises, n. 336).
c) An obvious pursuit of monetary gain in relation with the fact.
d) Gravely immoral acts committed by the subject, or his associates, at the time of the facts, or on the occasion of these facts.
e) Psychic disorders or psychopathic tendencies concerning the subject, which would exert an unquestionable influence on the allegedly supernatural facts, or indeed psychosis, mass hysteria, or other factors of the same kind.
It is important to consider these criteria, whether they are positive or negative, as indicative standards and not as final arguments, and to study them in their plurality and in relation with the other criteria.