Evidentiary rulings are reviewed under an abuse of discretion standard.  State v. Edwards, 485 N.W.2d 911 (Minn. 1992).  In order to warrant reversal, however, any error must have affected the substantial rights of the party claiming error. This is what is referred to as the harmless error rule.  The harmless error rule is embodied in Rule 103(a), which states: “[e]rror may not be predicated upon a ruling which admits or excludes...