Legal Definitions - major-and-minor fault rule

The major-and-minor fault rule is a legal principle primarily applied in admiralty (maritime) law to determine liability when two or more parties are at fault for an incident, such as a collision between vessels. This rule provides that if one party's fault is clearly substantial and directly contributed to the incident (the "major fault"), and the other party's fault is comparatively slight, technical, or doubtful in its contribution (the "minor fault"), the party with the minor fault may be excused from liability, or their fault may be disregarded. The rule aims to prevent a party whose minor infraction had little to no bearing on the outcome from being held equally responsible when another party's significant negligence was the overwhelming cause.

Here are some examples illustrating the major-and-minor fault rule:

• Example 1: Commercial Shipping Collision

  A large cargo ship is navigating through a busy shipping lane at night. The ship's crew fails to maintain a proper lookout, neglecting to use radar or visually scan the area, which is a serious violation of maritime safety regulations. As a result, the cargo ship collides with a smaller fishing trawler. The fishing trawler, while otherwise operating safely, had one of its navigation lights slightly dimmer than the regulatory standard, a minor technical infraction that did not significantly impair its visibility.

  How this illustrates the rule: The cargo ship's failure to maintain a proper lookout is the major fault because it was a direct and substantial cause of the collision. The fishing trawler's slightly dim navigation light is the minor fault; it was a technical violation but likely had little to no impact on the collision given the cargo ship's complete failure to observe. Under the major-and-minor fault rule, the cargo ship would likely bear the overwhelming, if not sole, responsibility for the collision.

• Example 2: Recreational Boating Accident

  A powerful speedboat is operating at an excessive speed in a clearly marked "no-wake" zone near a crowded marina. The speedboat operator is distracted and not paying attention to other vessels. It collides with a small sailboat that was slightly outside the designated channel markers, a minor deviation from its intended course, but was otherwise sailing cautiously and within speed limits.

  How this illustrates the rule: The speedboat's reckless speed and inattention in a restricted area constitute the major fault, as this behavior directly led to the dangerous collision. The sailboat's slight deviation from the channel is the minor fault; while a technical infraction, it was not the primary cause of the accident. The major-and-minor fault rule would likely place the primary blame on the speedboat operator due to their egregious negligence.

• Example 3: Port Maneuvering Incident

  A tugboat is assisting a large container ship in docking at a port. The tugboat operator makes a significant miscalculation in the maneuver, causing the container ship to strike the pier with considerable force, resulting in structural damage to the dock. A dock worker, earlier in the day, had left a small, non-critical piece of equipment slightly outside its designated storage area on the pier, a minor breach of port safety protocols, but it was not in the path of the ship and played no role in the collision.

  How this illustrates the rule: The tugboat operator's substantial error in maneuvering the container ship is the major fault, as it directly caused the damage to the pier. The dock worker's minor infraction of leaving equipment slightly out of place is the minor fault, as it had no causal connection to the ship striking the pier. The major-and-minor fault rule would likely assign full responsibility for the damage to the tugboat operator's negligence.