In the case of McDermott International, Inc. v. Jon C. Wilander (1990), the US Supreme Court ruled that a worker does not need to aid in navigation or contribute to a vessel's transportation mission to be considered a "seaman" under the Jones Act, which provides certain protections and rights for maritime workers injured on the job. The court held that any worker who is assigned permanently to a vessel or performs substantial work aboard it may qualify as seaman status regardless of their specific duties onboard. This decision came after Jon C.Wilander filed suit against his employer, McDermott International Inc., seeking damages for injuries he sustained while working on one of its vessels but was denied by lower courts due to his role being non-navigational.

In the dissenting opinion for McDermott International, Inc. v. Jon C. Wilander, it was argued that the majority's decision to extend seaman status under the Jones Act to workers who are not involved in a vessel's navigation or contribute to its function as a means of transport is inconsistent with both historical understanding and statutory intent of Congress when they enacted this law. The dissenters believed that by broadening the definition of "seaman," it could potentially include any worker aboard any type of floating structure regardless if their duties were related directly to maritime transportation or not, which would be contrary to what Congress intended when drafting this legislation - protection specifically for sailors and other traditional sea-going personnel against risks associated with their unique employment on navigable waters.