Here is what the Louisiana law is.. Seems to exclude anything over 26 feet or any boat with lifelines and stancheons:
RIDING ON DECKS AND GUNWALES:
No person operating a motor boat of twenty-six or less feet in length shall allow any person to ride or sit on either the starboard or part gunwales thereof or on the decking over the bow of the vessel while underway unless such motorboat is provided with adequate guards or railing to prevent passengers from being lost overboard.
This activity makes it easy to fall from a boat and leads to serious injuries and death in many cases.
RIDING ON DECKS AND GUNWALES:
No person operating a motor boat of twenty-six or less feet in length shall allow any person to ride or sit on either the starboard or part gunwales thereof or on the decking over the bow of the vessel while underway unless such motorboat is provided with adequate guards or railing to prevent passengers from being lost overboard.
This activity makes it easy to fall from a boat and leads to serious injuries and death in many cases.