Alcohol fueled one punches to (possibly) alcohol filled victims who hit their heads in a fall, as a result. Some ARE random victims.
Point is. had they not consumed alcohol, they may not have argued and fought. It's not the argument that killed anyone (stick and stones .......) it was the bad judgement, (which may have been alcohol fulled) that led to the punch, that killed the victim. NW - alcohol, argument, bad judgment to leave the boat, accident - death. No ones fault!