Friday, Feb 5, 2021 By the time Christopher Miller showed up at his estranged wife’s backdoor in September 2019 with a pistol in his waistband, state authorities already had declared him too dangerous to own firearms. He had lost his gun license 20 months earlier after being charged with aggravated battery for brutally beating a man in a Naperville parking lot. He disregarded orders to relinquish any weapons, and no one made sure he complied. Miller startled his wife that autumn afternoon as she moved around the kitchen making a snack for her daughter. With cocaine and alcohol in his system, he stared at Cassandra Tanner Miller with hazel eyes so dilated they appeared black.