The law is full of uniquely named rules. They’re often assigned names that correspond with the case in which the legal principle first arose. For instance, for maritime there’s the Pennsylvania Rule, the Walker doctrine, the economic loss rule, the Jensen doctrine and so on.

The Walker doctrine, also known as the Primary Duty Rule, bars a claimant’s recovery under the Jones Act. Walker is triggered when an injury to a ship’s officer or supervising crewmember was caused by that person’s conscious failure to maintain a safe condition aboard the vessel. For instance, an officer that drops a cylinder sleeve on his foot because he tried to carry it by himself instead of using a handcart might face a Walker problem.

When you tee up the Pennsylvania Rule it produces what we call a rebuttal presumption. In other words, when this rule applies it doesn’t necessarily bar your recovery, but it does tilt the table against you. This rule states that a party to a vessel collision who is also in violation of a statute is presumed to have caused the collision. You can upend the presumption by showing that the violation could not have caused or contributed to the collision. And one other thing, the statute being violated must be the sort designed to prevent collisions, meaning that only certain specific violations trigger this rule and not just any old violation.

If some local agency is pushing you around, you might want to give the Jensen doctrine a read-through. Jensen works to bar any state actor from implementing a law that interferes with or is otherwise contrary to the general maritime law. However, Jensen is a slippery character and its application is not easy to define. It’s also important to understand that not all state regulation of maritime activities is void. For example, where state law supplements maritime law, it might just be that the state law is permitted to coexist.

All of this legal shorthand is complicated and riddled with exceptions and qualifications, which is why it’s always wise to speak with an admiralty attorney.

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