Ex necessitate rei

EX NECESSITATE REI. From the necessity of the thing. Many acts may be done ex necessitate ret, which would not be justifiable without it; and sometimes property is protected, ex necessitate rei, which, under, other circumstances, would not be so. For example, property put upon the land of another from necessity, cannot be distrained for rent. See Distress; Necessity.

A Law Dictionary, Adapted to the Constitution and Laws of the United States. By John Bouvier. Published 1856.