(2): Magna Carta and arbitrary commitment.

A second erroneous theory has still to be discussed. The Petition of Right, as already stated, treats Magna Carta as prohibiting the Crown from making arrests without a warrant showing the cause of detention; and the earlier commentators further interpreted it as making all acts of arbitrary imprisonment by the Crown absolutely illegal. Hallam, for example, declares that “It cannot be too frequently repeated that no power of arbitrary detention has ever been known to our constitution since the charter obtained at Runnymede.” Yet every King of England from John Lackland to Charles Stewart claimed and exercised the prerogative of summarily committing to gaol any man suspected of evil designs against Crown or Commonwealth. Even the famous protest of the judges of Queen Elizabeth, asserting the existence of legal limits to the royal prerogative of commitment, proves the lawfulness of the general practice to which it makes exceptions. Such rights inherent in the Crown were never seriously challenged until the struggle between Charles I. and his parliaments had fairly begun. Then only was it suggested that Magna Carta was intended to prohibit arbitrary commitments at the command of the Crown. Such was the argument deliberately put forth in 1627 during the proceedings known sometimes as Darnell’s case and sometimes as the case of the Five Knights. Health, the Attorney–General, easily repelled this contention: “the law hath ever allowed this latitude to the King, or his privy council, which are his representative body, in extraordinary cases to restrain the persons of such freemen as for reasons of state they find necessary for a time, without for this present expressing the causes thereof.” The parliamentary leaders, however, too grimly in earnest to be deterred by logic, were far from abandoning their error because Heath had exposed it. They embodied it, on the contrary, in the Petition of Right, which condemned the Crown’s practice of imprisoning political offenders “without any cause showed” (other than per speciale mandatum regis), as contrary to the tenor of Magna Carta—an effective contention as a political expedient, but unsound in law.