Final answer:
Establishing legal liability requires negligence as a proximate cause, but premeditation is not essential.
Step-by-step explanation:
Establishing legal liability requires several elements, but one of the essential factors is negligence as the proximate cause. Negligence refers to the failure to exercise reasonable care in a given situation. In legal terms, proximate cause means that the negligent act was the direct cause of the injury or damage suffered by the claimant.
Therefore, option b. premeditation of the act by one party is not essential in establishing legal liability. Premeditation implies intent and deliberate planning, which may be relevant in certain cases but is not a necessary element in every legal claim.
For example, in the counter example situation provided, the manufacturer's liability for injuries and deaths was based on their knowledge of the defect and the likelihood of brake failure, not on premeditation of the act.