This annual assembly of parliament was rendered necessary, in the first place, by the strict appropriation of the revenue according to votes of supply. It was secured next, by passing the mutiny bill, under which the army is held together, and subjected to military discipline, for a short term, seldom or never exceeding twelve months. These are the two effectual securities against military power; that no pay can be issued to the troops without a previous authorisation by the Commons in a committee of supply, and by both houses in an act of appropriation; and that no officer or soldier can be punished for disobedience, nor any court martial held, without the annual re-enactment of the mutiny bill. Thus it is strictly true that, if the king were not to summon parliament every year, his army would cease to have a legal existence; and the refusal of either house to concur in the mutiny bill would at once wrest the sword out of his grasp. By the bill of rights, it is declared unlawful to keep any forces in time of peace without consent of parliament. This consent, by an invariable and wholesome usage, is given only from year to year; and its necessity may be considered perhaps the most powerful of those causes which have transferred so much even of the executive power into the management of the two houses of parliament. _Law of treason._--The reign of William is also distinguished by the provisions introduced into our law for the security of the subject against iniquitous condemnations on the charge of high treason, and intended to perfect those of earlier times, which had proved insufficient against the partiality of judges. But upon this occasion it will be necessary to take up the history of our constitutional law on this important head from the beginning.