What is the punishment for shaken baby syndrome ? In People v. Lefler, 38 Ill. 2d 216, 218, 230 N.E.2d 827 (1967), the defendant's infant daughter died with a skull fracture, extensive brain injury and rib injuries. Lefler, 38 Ill. 2d at 218. The defendant admitted to shaking and squeezing his daughter to get her to stop crying and could have broken her ribs in the process. Defendant was convicted of involuntary manslaughter. Lefler, 38 Ill. 2d at 222.