U.S. v. Boros

In prosecution on drug conspiracy charges, Dist. Ct. erred in admitting evidence from state's expert regarding physical side effects associated with individuals ingesting drugs sold to them by defendant since, although expert's testimony had some relevance on background evidence concerning regulatory scheme pertaining to prescription drugs and dangers that could result from sale of said drugs without medical supervision, said testimony was unduly prejudicial given minimal probative value with respect to elements of charged offenses. However, error was harmless given overwhelming nature of evidence establishing defendant's role in scheme to smuggle and then illegally sell controlled substances without requiring customers to provide prescriptions.