Constructive treason

Constructive treason is the judicial extension of the statutory definition of the crime of treason. For example, the English Treason Act 1351 declares it to be treason "When a Man doth compass or imagine the Death of our Lord the King." This was subsequently interpreted by the courts to include imprisoning the king, on the ground that history had shown that when a king is held captive by a usurper, he often dies in captivity. Despite legislative efforts to restrict the scope of treason, judges and prosecutors in common law jurisdictions still succeeded in broadening the reach of the offence by "constructing" new treasons. It is the opinion of one legal historian that:

The word “constructive” is one of the law’s most useful frauds. It implies substance where none exists. There can be constructive contracts, constructive trusts, constructive fraud, constructive intent, constructive possession, and constructive anything else the law chooses to baptize as such. “Constructive” in this sense means “treated as.” ... Constructive treason wasn’t “real” treason but a vaguely defined, less potent category of conduct that the court deciding the particular case felt should be “treated as” treason. It was the perfect instrument of oppression, being virtually whatever the authorities wanted it to be.

Ironically, the first attempt to constrain the development of constructive treasons in England was the 1351 Act itself. Its preamble states that Parliament had decided to define treason by statute for the first time because the common law definition had expanded so widely (however this had not been constructive treason, since until 1351 treason had always been defined by judges, not by legislation). The Act ended with a clause which prohibited further judicial development of the offence:

And because that many other like Cases of Treason may happen in Time to come, which a Man cannot think nor declare at this present Time; it is accorded, That if any other Case, supposed Treason, which is not above specified, doth happen before any Justices, the Justices shall tarry without any going to Judgement of the Treason till the Cause be shewed and declared before the King and his Parliament, whether it ought to be judged Treason or other Felony.

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