Mealey's (August 20, 2020, 12:01 PM EDT) -- ST. LOUIS — While a federal court erred in the way it allowed a police officer to give both expert and lay testimony at the trial of an Iowa man for selling heroin, the mistake was harmless because there was ample other evidence to convict him, the Eighth Circuit U.S. Court of Appeals concluded Aug. 19 (United States v. Thomas D. Overton, No. 19-2574, 8th Cir., 2020 U.S. App. LEXIS 26280)....