The defendant’s action must be both the cause in fact and the legal cause of an injury. Cause in fact is established if the injury would not have occurred but for the defendant’s actions. Legal cause, or proximate cause, requires that the injury be a foreseeable result of the action. Courts often use the ‘foreseeability test’ to determine if the harm was predictable and thus should have been reasonably anticipated by the defendant.
For example: If a store owner leaves a spill unattended and a customer slips and is injured, the owner’s failure to clean up can be cited as both the cause in fact (the injury wouldn’t have occurred if the spill were cleaned) and the legal cause (it is foreseeable that someone might slip on an unattended spill).