My BIL and I would actually go at it with each other about stuff like this. His twins were crazy when they were little. Daredevils. I would alwats tell at them to put their helmets on riding their bikes, and my BIL would get mad and tell me how we managed to survive childhood without all these safety precautions. (I guess he didn't realize we were the lucky ones).
My niece got hit by a car and was thrown 50 ft and landed on her head on the pavement. She was in a coma for 2 weeks, and we didn't even know if she would even wake up, let alone what we would be left with if she did. the trauma to her brain was horrendous. the Doctors could not tell us much, because it would be giving us hope in what they felt was a losing battle. By the Amazing Grace of God, she did wake up, and she is a normal 17 year old today. the Dr's were astounded at her recovery. It just didn't happen to someone with a head trauma as bad as hers was.
needless to say, my niece was still in the hospital when the trampoline came down, the boys got helmets, and from that day, they better of made sure the helmets were on their heads or my BIL would hit the roof.
Accident or not, if Ashely were YOUR child, it would not be called an accident. You would beat yourself up with guilt for years afterwards.