Can. 1620

A sentence suffers from the defect of irremediable nullity if:

1/ it was rendered by an absolutely incompetent judge;

2/ it was rendered by a person who lacks the power of judging in the tribunal in which the case was decided;

3/ a judge rendered a sentence coerced by force or grave fear;

4/ the trial took place without the judicial petition mentioned in can. 1501 or was not instituted against some respondent;

5/ it was rendered between parties, at least one of whom did not have standing in the trial;

6/ someone acted in the name of another without a legitimate mandate;

7/ the right of defense was denied to one or the other party;

8/ it did not decide the controversy even partially.