Chapter — Slater, Manual of Moral Theology
Chapter IV. Removal of Irregularities
As a general rule irregularities cease only by dispensation granted by the Holy See through the Sacred Congregation on . the Discipline of the Sacraments for the external forum, and through the Sacred Penitentiary for the internal forum.
p. ii, 292
Ordinaries personally or through another have power to dispense their subjects from all irregularities arising from occult crimes, except from voluntary homicide or the procuring of abortion with effect, and others brought before their judicial forum.
p. ii, 292
All confessors have the same power in more urgent occult cases in which not even the Ordinary can be approached, and there is danger of serious harm or loss of reputation, but only to enable a penitent to exercise lawfully the Orders which he has already received (Can. 990).
p. ii, 292
When there is a doubt of fact about an irregularity an Ordinary can dispense if the Holy See is accustomed to dispense in such cases (Can. 15).
p. ii, 292
The simple impediments cease on the total cessation of the cause or fact from which they arise, and by dispensation.
p. ii, 292
In the petition for a dispensation from irregularities and simple impediments all the irregularities and impediments in the case should be mentioned. A general dispensation will not avail for those not mentioned in bad faith.
p. ii, 292