Felix Frankfurter,
Rosenberg v. United States (360 U.S. 367…
“ An appellate court should not confidently guess what defendant's attorney might have found useful for impeachment purposes in withheld documents to which the defense is entitled. However, when the very same information was possessed by defendant's counsel as would have been available were error not committed, it would offend common sense and the fair administration of justice to order a new trial. There is such a thing as harmless error and this clearly was such. The judgment of the Court of Appeals for the Third Circuit is therefore affirmed. ”
