Explain the role of 'proximate cause' in establishing causation, and provide an example where an intervening cause breaks the chain of causation.

'Proximate cause' is a critical element in establishing causation in criminal law. Causation, in general, requires a link between the defendant's actions and the resulting harm or injury. 'Proximate cause' limits liability to harms that are a foreseeable or natural consequence of the defendant's act. It essentially asks whether the defendant's action was a substantial factor in bringing about the result and whether the result was reasonably foreseeable. It goes beyond the 'but-for' test, which simply asks whether the harm would have occurred 'but for' the defendant's action. 'Proximate cause' introduces a fairness consideration: even if the defendant's action started a chain of events, they should not be liable for completely unforeseeable outcomes. An 'intervening cause' is a separate event that occurs after the defendant's initial act and contributes to the resulting harm. If the intervening cause is deemed to be 'superseding' – meaning it was unforeseeable and independent of the defendant's actions – it can break the chain of causation, relieving the defendant of criminal liability. For example, if a defendant punches a victim, causing a minor injury, and the victim is then taken to a hospital where a negligent doctor administers the wrong medication, leading to the victim's death, the doctor's gross negligence could be considered a superseding intervening cause. In this scenario, while the initial punch was a 'but-for' cause of the death (the victim wouldn't have been at the hospital without it), the doctor's unforeseeable and grossly negligent act would break the chain of proximate causation, potentially shielding the defendant from being held liable for homicide, but not the initial battery.