But disinheritance, as well as disregard, of his children imperilled the will. As next heirs on an intestacy they could complain to the Court that the will failed in the due regard which a sane man would shew to his children. This was the "plaint of an unduteous will" (querela inofficiosi testamenti). If complainant established his case, the will with all its legacies and gifts of freedom drops and intestacy results. To establish his case he has to prove three things: that his conduct did not justify disinheritance, that he did not get under the will (e.g. by legacy) at least one-fourth of the share of the inheritance to which he would have been entitled under an intestacy, and that he had not in any way shewn an acceptance of the will as valid. Parents could in the same way complain of their children's wills, and brothers and sisters of the testator could complain of his will, if the heirs appointed were disreputable. An illegitimate child could complain of his mother's will. If complainant had judgment given against him, he lost anything given him by the will. An analogous complaint was allowed against excessive donations which unfairly diminished a child's or parent's claim.
The value of the estate is taken for this purpose as for the Falcidian fourth. Justinian in 528 enacted that if complainants had been left something but not enough, the deficiency could be supplied without otherwise upsetting the will, provided testator had not justly charged them with ingratitude. In 536 Justinian raised the share of the inheritance which would exclude the plaint to one-third, if there were four or fewer children, and to one-half if there were more than four, i.e. to one-third or one-half of what would be claimant's share on an intestacy. Thus supposing two children, each would now be entitled to one-sixth (instead of one-eighth) of the estate: if three children, to one-ninth: if five, to one-tenth, and so on. Such share is called "statutory portion" (portio legitima) and could be made up either by an adequate share of the inheritance, or by legacy, or through a trust, or by gift intended for the purpose or by dowry or nuptial gift or purchaseable office in the imperial service (militia), or a combination of such. This statutory portion becomes in French law "legitim," in German "Pflichttheil."
In 542 Justinian put the matter on a new footing by requiring children to be actually named as heirs in their father's or mother's or other ascendant's will, unless the will alleged as the cause of disherison "ingratitude" on one at least of certain grounds, and the heirs prove the charge to be true. These grounds are: laying hands on parents, gravely insulting them, accusation of crimes (other than crimes against the Emperor or the State), associating with practisers of evil acts, attempting parent's life by poison or otherwise, lying with step-mother or father's concubine, informing against parents to their serious cost, refusing, if a son, to be surety for an imprisoned parent, hindering his parents from making a will, associating with gladiators or actors against his parent's
