Obreption

[…]the irregularities of the first motions, violent assaults, and importunities of temptations, sudden incursions, and obreptions, sins of mere ignorance and inadvertency […]

In Mr John Maitland's action against Cardross, (vide 17th instant,) the Lords repelled Cardross's allegeances founded upon the impetrating of the gift of eschat from his Majesty by obreption expresso mendacio, or subreption celata veritate; because it appeared that there was a competition made by Cardross before the gift was past in Exchequer, and this same objection was made against it, that it was impetrated viis et modis;

A dispensation from a minor impediment is not vitiated by obreption or subreption, even though the final cause alleged be false.