My brother injured his knee as he fell wakeboarding. My step-father knowingly exceeded the recommended speed for a beginner boarder. Where does the liability lie? My brother's medical insurance will pay for everything in full, but won't they want to go after the boat insurance? please advice!

as the injury is reasonable for the sport he was engaged in. you have no evidence that the injury was caused by excess speed. he could have been injured the same way at a lower speed. If he felt the speed was too fast, all he had to do was let go of the rope. but he continued to ride the wake board. By doing so he assumed any and all risks associated with the activity. so you might lose in the court.