Amy Senser will testify in her own defense at her vehicular homicide trial. Her stepdaughter, though, will testify for the prosecution. In opening arguments, a prosecutor said the stepdaughter - worried that she was becoming a suspect - demanded that Amy Senser tell authorities who was driving the SUV that struck and killed a man on an I-94 exit ramp last summer. Amy Senser says she was unaware her vehicle had hit the man.