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A formal written allegation of the causes for impeachment; answering the same office as an indictment in an ordinary criminal proceeding.

An instrument which, in cases of impeachment, (q. v.) is used, and performs the same office which an indictment does, in a common criminal case, is known by this name. These articles do not usually pursue the strict form and accuracy of an indictment., Wood. Lect. 40, p. 605; Foster, 389, 390; Com. Dig. Parliament, L 21. They are sometimes quite general in the form of the allegations, but always contain, or ought to contain, so much certainty, as to enable the party to put himself on the proper defence, and in case of an acquittal, to avail himself of it, as a bar to another impeachment. Additional articles may, perhaps, be exhibited at any stage of the prosecution. Story on the 806; Rawle on the Const. 216.

The answer to articles of impeachment is exempted from observing great strictness of form; and it may contain arguments as well as facts. It is usual to give a full and particular answer to each article of the accusation. Story, 808.