The founders of the English laws have with excellent forecast contrived, that no man should be called to answer to the king for any capital crime, unless upon the preparatory accusation of twelve or more of his fellow subjects, the grand jury: and that the truth of every accusation, whether preferred in the shape of indictment, information, or appeal, should afterwards be confirmed by the unanimous suffrage of twelve of his equals and neighbours, indifferently chosen, and superior to all suspicion. So that the liberties of England cannot but subsist, so long as this palladium remains sacred and inviolate, not only from all open attacks, (which none will be so hardy as to make) but also from all secret machinations, which may sap and undermine it; by introducing new and arbitrary methods of trial, by justices of the peace, commissioners of the revenue, and courts of conscience. And however convenient these may appear at first, (as doubtless all arbitrary powers, well executed, are the most convenient) yet let it be again remembered, that delays, and little inconveniences in the forms of justice, are the price that all free nations must pay for their liberty in more substantial matters; that these inroads upon this sacred bulwark of the nation are fundamentally opposite to the spirit of our constitution; and that, though begun in trifles, the precedent may gradually increase and spread, to the utter disuse of juries in questions of the most momentous concern.

William Blackstone (1723-1780) British jurist, judge, politician

Commentaries on the Laws of England, Book 4, ch. 27 “Of Trial, And Conviction”(1765-1769)
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