by John Marshall Harlan

“ A 'claimant' or a 'plaintiff' in the Court of Claims is incompetent as a witness against the United States. Is not Clark a 'plaintiff,' and does he not in this suit set up a claim or right? If allowed to be a witness to prove the amount of his loss, will he not give testimony in support of a 'right' to be credited therewith? Is not the act explicit and imperative that no 'plaintiff' shall be heard to support his claim or right in that court by his own testimony, and that his testimony shall not be used against the government? ”

“ He is thus allowed to establish, by his own testimony, one of the essential facts upon which any decree in his favor must rest; viz., the amount for which he should receive credit in the settlement of his accounts.
In that view I cannot concur. I think it cannot be sustained upon principle or authority. The will of Congress as to the conditions upon which it allows the citizen to sue the government has been expressed in plain and unambiguous language, which leaves no room for construction. ”

“ That eminent text-writer says that 'the oath in litem is admitted in two classes of cases: first, when it has been already proved that he party against whom it is offered has been guilty of some fraud or other tortious and unwarrantable act of intermeddling with the complainant's goods, and no other evidence can be had of the amount of damage ”