A judge may not serve as a witness at the trial over which he or she presides.

United States v. Bakhtiar, 994 F.2d 970, 979 (2d Cir. 1993) (convictions for conspiracy, bank fraud, wire fraud, money laundering, illegal monetary transactions using the proceeds of criminal activity, and possession....A duplicate of an original is admissible to the same extent as the original if (1) there is no genuine question about the authenticity of the original, and (2) admission of the duplicate in lieu of the original is not unfair.

Cf. Winningham v. Travelers Insurance Co., 93 F.2d 520, 521 (5th Cir. 1937) (holding, in plaintiff survivors' action against defendant insurance company for compensation after the death of an assembly plant employee, that evidence of....Federal Rule of Evidence 409 or a comparable State rule bars evidence that a party paid for or furnished medical, hospital, or similar expenses for an injury if such evidence is offered to show the party's liability for the injury.

United States v. Naylor, 705 F.2d 110, 111-112 (4th Cir. 1983) (upholding trial court's admission of evidence of accused's 1980 conviction for attempted theft of a motor vehicle because it constituted a prior similar act which proved his knowledge that the vehicle was stolen, as an essential element of...A person's other crimes, wrongs, or acts are not barred by the character rule either if they are not offered to show that person's propensity or if they are not offered to show that that person engaged in conduct on a particular occasion because of his or her propensity to engage in that sort of conduct.