I have no doubt about that.
Once you add a canopy to an open runabout, there is no way that the standard white light provided by the manufacturer will be seen through 360º.
Likewise, once you add a solid baitboard at the back, same thing.
I used to worry about this when I have been night fishing, more so because I don't want to be unseen on the water because of the canopy than because of potential problems with the police, so when I fish at night, I always plonk a bodgied up portable light on top of my canopy with a lead that plugs into a cigarette lighter socket on the boat.
As you can see from the picture, this is as uncomplicated as it gets - a small white nav light screwed to a plastic box with a cord coming out of it at the end of which is a plug.
Very cheap to do. Works a treat. When I fish at night, I am completely legal and visible in all weather.
The additional benefit of this arrangement is that because the light sits on top of my canopy, it does not invade my eyes nor shine down on the water close to my boat. I usually pull out the normal white light on its stem from the back of the boat (to be replaced when underway again) such that I have one less encumbrance in the way when I fish out the back of the boat.
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