A woman who claimed Zion police officers used excessive force during a 2014 arrest was denied a fair trial when she was not allowed to show evidence of a past police encounter, a federal appeals panel ruled.The 7th U.S. Circuit Court of Appeals ruled Friday U.S. Magistrate Judge Sheila M. Finnegan abused her discretion when she granted the city of Zion’s motion barring evidence regarding plaintiff Kasey Burton’s …