Causation

Courts usually split causation into two questions:

• Cause in fact — would the harm have happened without the defendant's conduct? (The 'but-for' test)
• Proximate cause — was the harm a foreseeable result of the conduct, not a remote or bizarre chain of events?

Causation is often the softest spot in an injury claim. Even if fault is clear, the insurer can argue the claimed injury wasn't actually caused by this event. Pre-existing back pain, degenerative disc disease, prior car accidents, prior falls — any of these can be used to argue the current complaints would have happened anyway. Medical records that predate the injury become central.

A long-standing rule says a defendant takes the injured person as they find them. If the person had a fragile neck and an otherwise mild crash caused serious injury, the defendant is still responsible for the full harm — even if a healthier person would have walked away. The rule softens the 'it would have happened anyway' argument, though insurers still argue about how much damage was really caused versus pre-existing.

In serious cases, proving causation often requires medical expert testimony — a doctor saying, within a reasonable degree of medical certainty, that the injury was caused or aggravated by the incident. Without that testimony, complex causation questions are difficult to win.