justifiable

That can be justified.

Near-synonyms: defensible, excusable

It was at all times clear that, from the point of view of the idea it conveys to us, every motion must be considered only as a relative motion. Returning to the illustration we have frequently used of the embankment and the railway carriage, we can express the fact of the motion here taking place in the following two forms, both of which are equally justifiable: (a) The carriage is in motion relative to the embankment, (b) The embankment is in motion relative to the carriage. In (a) the embankment, in (b) the carriage, serves as the body of reference in our statement of the motion taking place. —

Describing an illegal and intentional act that is nevertheless not blameworthy, for example because its positive consequences outweighed the bad. Distinguished from excusable, describing an involuntary illegal act.

justifiable homicide