“Statutes also are either declaratory of the common law, or remedial of some defects therein. Declaratory, where the old custom of the kingdom is almost fallen into disuse, or become disputable; in which case the parliament has thought proper, in perpetuum rei testimonium, and for avoiding all doubts and difficulties, to declare what the common law is and ever hath been.” 1 William Blackstone, Commentaries on the Laws of England 86 (1765).
in perpetuum rei testimonium
in perpetuum rei testimonium (in p[schwa]r-pech-oo-[schwa]m [or p[schwa]r-pe-tyoo-[schwa]m] ree-I tes-ti-moh-nee-[schwa]m), adv. [Law Latin] In perpetual testimony of a matter. • This phrase refers to a statute that confirms existing common law.
