“The disqualifications formerly attaching to witnesses, and especially that of relationship, were sometimes disregarded in occult or private facts, where there must, from the nature of the case, be a scarcity of unexceptionable witnesses …. It was not enough in this sense, to constitute a penuria testium, to prove that the other evidence was scanty and defective; it had to be shown farther that the penuria was necessarily occasioned by the very nature of the question at issue.” William Bell, Bell’s Dictionary and Digest of the Law of Scotland 798 (George Watson ed., 7th ed. 1890).
penuria testium
penuria testium (p[schwa]-nyoor-ee-[schwa] tes-tee-[schwa]m). [Latin] Hist. A scarcity of witnesses.