It's all going to depend on state law, so what goes on Lake Havasu does not mean anything in Colorado. I don't know if there is a law about paddling impaired, but I can't see anyone getting convicted because they were the "propulsion" for a boat. Laws are required to be more specific than that, so if it doesn't say something to that effect, it wouldn't apply. On the civil side, if you were rowing drunk and an accident happened involving more than just you, there could very well be negligence issues.
Although we have lost an awful number of boaters this year, I'm unaware of any substance-related WW accidents that caused a death. (Although I do know a certain rather wasted RCRE official who had issues staying upright in the flatwater just above Hecla.) When I lived in Carolina, even the triple-crown regulars on the Green would only toke up after Sunshine. But come to think of it, I had an acquaintance in NC that once ran the Upper Gauley with Team "Really Big Kayak Company" and they had a little pre-run huddle. He thought they were gonna give a rundown to some newbies or maybe pass a hitter 'round. When he popped his head in, they were passing a crack pipe. Stranger than fiction...sorry to hijack a little...
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