[QUOTE=Steamer;58498]I
If someone on the boat does not “contribute to the function of the vessel or to the accomplishment of its mission, or have a connection to a vessel in navigation that is substantial in both its duration and its nature” then he has no role or responsibility on or to that vessel.
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That quote is from the Jones Act. That is only part of the criteria that was originally asked about. Being a vessels crew is separate and distinct from being a passenger. (paying or guest) The Jones Act only applies to the crew. A passenger cannot ‘make themselves’ a member of the crew (as in OPs worry) So one must understand both sides of the legal equation. A crew is able to be critiqued by the CG post accident. The passengers (even documented mariners) are not subject to the same critique. They may be interrogated or used as witness, but they are not held to the same level of responsibility as the crew.