"The 11th of Henry VII., though subsequent to these transactions, is full in point. For let it be remembered, that though the enacting part of this excellent law can respect only future cases, the preamble, which his Lordship doth not cite at large, is declaratory of the common law: and consequently will enable us to judge of the legality of past transactions. It reciteth to this effect, 'That the subjects of England are bound by the duty of their allegiance to serve their Prince and Sovereign Lord for the time being, in defence of him and his realm, against every rebellion, power, and might raised against him; and that whatsoever may happen in the fortune of war against the mind and will of the Prince, as in this land, some time past it hath been seen, it is not reasonable, but against all laws, reason, and good conscience, that such subjects attending upon such service should suffer for doing their true duty and service of allegiance.' It then enacteth, that no person attending upon the King for the time being in his wars, shall for such service be convict or attaint of treason or other offence by Act of Parliament, or otherwise by any process of law."
The author says then:
"Here is a clear and full parliamentary declaration, that by the antient law and Constitution of England, founded on principles of reason, equity, and good conscience, the allegiance of the subject is due to the King for the time being, and to him alone. This putteth the duty of the subject upon a rational, safe bottom. He knoweth that protection and allegiance are reciprocal duties. He hopeth for protection from the Crown, and he payeth his allegiance to it in the person of him whom he seeth in full and peaceable possession of it. He entereth not into the question of title; he hath neither leisure or abilities, nor is he at liberty to enter into that question. But he seeth the fountain, from whence the blessings of Government, liberty, peace, and plenty flow to him; and there he payeth his allegiance. And this excellent law hath secured him against all after reckonings on that account."
And another author on that subject [Hawkins], in his Pleas of the Crown, Book I., chap. 17, sec. 11, says:
"As to the third point, who is a King within this act? [26 Edw. 3, ch. 2.] It seems agreed that every King for the time being, in actual possession of the crown, is a King within the meaning of this statute. For there is a necessity that the realm should have a King by whom and in whose name the laws shall be administered; and the King in possession being the only person who either doth or can administer those laws, must be the only person who has a right to that obedience which is due to him who administers those laws; and since by virtue thereof he secures to us the safety of our lives, liberties, and properties, and all other advantages of Government, he may justly claim returns of duty, allegiance, and subjection."
"Sec. 12. And this plainly appears by the prevailing opinions in the reign of King Edward IV., in whose reign the distinction between a King de jure and de facto seems first to have begun; and yet it was then laid down as a principle, and taken for granted in the arguments of Bagot's case, that a treason against Henry VI. while he was King, in compassing his death, was punishable after Edward IV. came to the Crown; from which it follows that allegiance was held to be due to Henry VI. while he was King, because every indictment of treason must lay the offence contra ligeantiæ debitum.
"Sec. 13. It was also settled that all judicial acts done by Henry VI. while he was King, and also all pardons of felony and charters of denization granted by him, were valid; but that a pardon made by Edward IV., before he was actually King, was void, even after he came to the Crown."
"And by the 11th Henry VII., ch. 1, it is declared 'that all subjects are bound by their allegiance to serve their Prince and Sovereign Lord for the time being in his wars for the defence of him and his land against every rebellion, power, and might reared against him, &c., and that it is against all laws, reason, and good conscience that he should lose or forfeit any thing for so doing;' and it is enacted 'that from thenceforth no person or persons that attend on the King for the time being, and do him true and faithful allegiance in his wars, within the realm or without, shall for the said deed and true duty of allegiance be convict of any offence.'"
"Sec. 15. From hence it clearly follows: First, that every King for the time being has a right to the people's allegiance, because they are bound thereby to defend him in his wars, against every power whatsoever.
"Sec. 16. Secondly, that one out of possession is so far from having any right to allegiance, by virtue of any other title which he may set up against the King in being, that we are bound by the duty of our allegiance to resist him."