corroborate

corroborate \kuh-ROB-uh-rayt\, transitive verb:

To strengthen or make more certain with other evidence.

Whenever I can, I interview family and friends extensively both to corroborate the history given me by the defendant and to gain insight into his behavior and personality.
-- Barbara R. Kirwin, Ph.D., The Mad, the Bad, and the Innocent: The Criminal Mind on Trial

He said that when the jurors confronted discrepancies in any of the prosecution witnesses' descriptions, they used the testimony of other prosecution witnesses to corroborate the chronology.
-- "Most Jurors Thought Schwarz Aided Attack, Foreman Says", New York Times, August 2, 2002

As we have no public notoriety, no concurrent testimony, no records to support and corroborate what we deliver, it becomes us to keep within the limits not only of possibility, but of probability too.
-- Henry Fielding, The History of Tom Jones

Corroborate is from Latin corroboratus, past participle of the verb corroborare, "to strengthen," from com-, "with" + roborare, "to strengthen," and is related to robust.