They were both running on pad in the no wake zone. Front boat let off at the bridge and back boat had no idea it was gonna happen. Both were at fault of breaking a law that led up to the accident.
More than likely that would not be a plausible defense in a court of law, either civil nor criminal.
Yes the guy who got ran over was in violation prior to being run over, but had he began to comply to the regulation prior to the time he was ran over by the other boat?
His slowing down does not justify being ran over from behind. Perhaps he to would be sited for violation of a no wake zone prior to the collision, but the guy who was negligent doesn't get a free pass when the other dumb [censored] in front of him slows down. They were both wrong for running a no wake zone, but the dude that ran over the other boat would likely be at fault in the accident.
Simple "rule of the road" for water craft, "Overtaking: The vessel that is overtaking another vessel is the give-way vessel. The vessel being overtaken is the stand-on vessel"
All in all what a sh** show and a legal mess. Luckily nobody was killed.