United States v. Odom
United States Court of Appeals for the Fourth Circuit
736 F.2d 104 (4th Cir. 1984)
Odom and other defendants were charged with voter fraud for casting absentee ballots in the names of retirement-home residents; the prosecution called roughly 30 residents as witnesses, and the trial court denied the defense's motion for an in camera competency determination for each, declining to swear in nine witnesses it found unable to understand the questions posed. The defendants did not object to unsworn testimony until filing (and then withdrawing) a motion to strike the following day; they were convicted and appealed, arguing the residents' visible mental limitations improperly implied to the jury that the defendants must have committed fraud since the residents couldn't have made informed voting choices themselves.
Whether feeble-mindedness alone is sufficient grounds to disqualify a witness due to lack of competency.