A confirmation that reinforces an allegation, usually refers to evidence that makes it more likely that testimony given is truthful and based in fact.
Law Dictionary – Alternative Legal Definition
To strengthen; to add weight or credibility to a thing by additional and confirming facts or evidence. The expression “corroborating circumstances” clearly does not mean facts which, independent of a confession, will warrant a conviction; for then the verdict would stand not on the confession, but upon those independent circumstances. To corroborate is to strengthen, to confirm by additional security, to add strength. The testimony of a witness is said to be corroborated when it is shown to correspond with the representation of some other witness, or to comport with some facts otherwise known or established. Corroborating circumstances, then, used in reference to a confession, are such as serve to strengthen it, to render it more probable; such, in short, as may serve to impress a jury with a belief in its truth. State v. Guild, 10 N. J. Law, 163, 18 Am. Dec. 404. Corroborating: evidence. Evidence supplementary to that already given and tending to strengthen or confirm it; additional evidence of a different character to the same point. Gildersleeve v. Atkinson, 6 N. M. 250, 27 Pac. 477; Mills v. Comm., 03 Va. 815, 22 S. E. 863; Code Civ. Proc. Cal. 1003,