A plaintiff is injured when the defendant's motor vehicle swerves suddenly across a highway centerline and strikes the plaintiff's vehicle. The case seems to be one of open-and-shut liability: the plaintiff was injured through no fault of her own. However, an injury is not necessarily evidence of negligence, and the occurrence of an accident does not automatically entitle a plaintiff to a recovery. Some accidents are simply beyond the power of human intervention to prevent. For this reason, Illinois recognizes an act of God as an affirmative defense and basis for summary judgment.
An act-of-God defense applies when an unforeseeable and sudden illness renders a defendant incapable of controlling his vehicle and precludes liability for a resulting collision. In such rare circumstances, the loss is not recoverable because it “is occasioned exclusively by natural causes such as could not be prevented by human care, skill[,] and foresight.” Evans v. Brown, 399 Ill.App.3d 238, 246 (4th Dist. 2010); Grote v. Estate of Franklin, 214 Ill.App.3d 261, 271 (2d Dist. 1991) (holding an unforeseeable sudden illness that renders a defendant incapable of controlling his or her vehicle is an act of God and can preclude liability for a resulting collision). The defense applies most often when the defendant driver experiences a seizure, loss of consciousness, or death before his vehicle causes the plaintiff's loss. However, even when the defense can show that defendant driver suffered a sudden loss of control due to a condition of health, the act-of-God defense does not automatically preclude liability. Liability is only precluded if the asserted act of God was wholly unforeseeable and actually constitutes the sole and proximate cause of the claimed loss.
In short, the act-of-God defense applies in circumstances that where the defendant can be viewed as free of negligence. Thus, the requirement that the loss of control be unforeseeable means that liability may still attach for the driver who operated a motor vehicle with the knowledge that he has a medical condition that can cause him to lose control of his vehicle even when the condition was asymptomatic and the onset of the debilitating symptoms was sudden and unexpected. Burns v. Grezeka, 155 Ill.App.3d 294, 299 (2d Dist. 1987) (reversing summary judgment in part on grounds that defendant driver may be deemed negligent for driving with an abdominal aneurysm, which had been present for two or three years, even though his doctor testified that he would not have experienced any forewarning of the rupture that the defendant contended cause him to lose control over his vehicle).