10 Who entitled to the Prerogatives. [Ch. L troduced on grounds of political necessity. The general doc- trine, that all the daughters of the father, who died seised, are entitled to his estate, on failure of a male heir (a), does not apply to the descent of the Crown; so that the eldest daughter of the last King is, under such circumstances, exclu- sively heiress to the throne, {h) So the rule of possessio fratris does not hold on the descent of the Crown; nor is half-blood any impediment in such case. Therefore, if a King has issue a son and a daughter, by one venter, and a son by another venter, and die ; on the death of the eldest son without issue, tlie younger brother is entided to the Crown, to the exclusion of the daughter, (c) Even the doctrine which antiently prevailed in the law of descents, that when the eldest son was already provided for, the next brother should take the rest of their father's inheritance, was never adopted as a rule of public succession, [d) It should however be remarked, that even a King de Jacto^ or one in the actual exercise of sovereignty, whilst he remains on the dirone, is bylaw entitled to the royal prerogatives; {e) and is so far King that treason may, legally speaking, be committed against him. [f) The doctrine is grounded on the maxim, protectio trahit suhjectionem et suhjectio protec' tionem : (g) and though it evidently contradicts a very com- mon principle, that no one shall avail himself of his own wrong, it appears to be in a political point of view highly reasonable. It is indeed a political principle instituted for the safety and benefit of the people, whose loyalty may be repressed by the overwhelming power of an usurper. And Sir M, Foster {h) speaking of a King de jure and de facto, and contending that allegiance is due from the subject to the latter as well as the former, observes : " He (the subject) hopeth for protection from the Crown, and he payeth his allegiance to it, in the person of him whom he seeth in full and peace- able possession of it: he entereth not into the question of (a) See Lit. sect. 241. SeeKelyng, 14. 1 Keb. 315. 15ro. Ab. lb) Co. Lit. 15. b. 7 Co. 12. b. 1 Bla. tit. Charter de pardon, pi. 22. 2 Wooddn. Com. 194. 1 Wooddn. 69. 502, 3. (c) Plowd. 245. 4 Inst. 206. Co. Lit. (/) 1 Hawk, P. C Bk. 1. c. 17. s. 11. 15. b. 1 Wooddn. 69. Hal. Hist. P. C. 102. 4 Bla. Com. 77. (d) 1 Bla. Com. 200. (g) 7 Rep. 5. (e) Foster, Cr, Law, 188. 399. 402. (Ji) Foster, Cr. L. 399. title,
