Prosecutors say 25-year-old Cory Mullen of Clinton Township is trying to game the system. Mullen has been charged with the fatal shooting of 21-year-old Jamilia Vigier-Cage, who is the mother of Mullen’s child. Her body was found last March in a car parked on Industrial Road in Troy. An Oakland County Circuit Court judge granted Mullen’s motion last week that he undergo an independent examination to determine if he is competent to stand trial. Prosecutors note that he has already undergone two forensic psychiatric exams at the Human Services Center for Forensic Psychiatry and, in both cases, it was determined that he was actively engaged in an effort make himself seem incompetent. The results lead prosecutors to believe Mullin may use an insanity plea in his defense, but Mullen’s attorney has not filed the motion.