Black's Law Dictionary (2nd edition)dictionaries

Virtue

The phrase “by virtue” differs in meaning from “under color.” For instance, the proper fees are received bg virtue of the office; extortion is under color of the office. Any rightful act in office is by virtue of the office. A wrongful act in office may be nnder color of the office. Phil. Law, 380

Source: Black’s Law Dictionary 2nd Ed (1910)