Appellant, Joseph Isisah Long, a/k/a David Munds (Long), was convicted of three offenses: (1) possession of heroin; (2) possession of a firearm while in possession of heroin (firearm/heroin); and (3) possession of a firearm after having been convicted of a felony (firearm/felony). Although the charges against Long all stemmed from a single transaction, we hold that the trial court erred in refusing to sever the firearm/ felony charge from the other two charges because Justice required severance under Rule 3A:10(b).