Source: http://www.vatican.va/archive/ENG1104/_P6F.HTM
Timestamp: 2019-04-19 14:33:19+00:00

Document:
Can. 1645 §1. Restitutio in integrum is granted against a sentence which has become res iudicata provided that its injustice is clearly established.
5/ the sentence is contrary to a previous decision which has become res iudicata.
Can. 1646 §1. Restitutio in integrum for the reasons mentioned in ⇒ can. 1645, §2, nn. 1-3 must be sought from the judge who rendered the sentence within three months computed from the day the person became aware of these same reasons.
§2. Restitutio in integrum for the reasons mentioned in ⇒ can. 1645 §2, nn. 4 and 5 must be sought from the appellate tribunal within three months from the notice of the publication of the sentence; if in the case mentioned in ⇒ can. 1645, §2, n. 5 notice of the previous decision occurs later, however, the time limit runs from this notice.
Can. 1647 §1. The petition for restitutio in integrum suspends the execution of a sentence if execution has not yet begun.
§2. If from probable indications there is a suspicion that a petition has been made in order to delay the execution, however, the judge can decree execution of the sentence, though with suitable guarantees to the one seeking the restitutio that there will be indemnity if the restitutio in integrum is granted.
Can. 1648 If restitutio in integrum is granted, the judge must pronounce on the merits of the case.

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