Wouldn’t it all just be a lot easier if we all just took on some personal responsibility for once?
The issue is that an individual might not foresee the risk of doing something because they don’t have all the information. To take the case to an extreme hypothetical level, what if it had been some random rambler and the course wasn’t taped at all with no marshals? At some point between that scenario and “100ft [run off areas] and a bigger fence?” you can draw up a set of best practices that keep people safe as far as reasonably practical. That last bit’s the important bit in almost all H&S matters, you accept there is a risk but you take all reasonable steps to avoid/mitigate it.
What does prosecuting an individual in this case achieve?
I’m going to suggest all it achieves is to ruin another persons life, and potentially, should that prosecution lead to a, very likely imo, lack of volunteer marshals for events, to prevent a lot of people from getting a lot of enjoyment out of a sport they love.
Well, no. If you are doing a job and mess up because you didn’t do it as you should then something has gone wrong. That could be he was just bad at it (his own fault) or because he wasn’t given adequate training (his employers fault). The HSE’s investigation will hopefully have identified which of those they think it is (presumably the marshal otherwise it would just be the employer/organizer on trial).
For the past week I’ve been putting up scaffold towers to rig for a TV show. Now if one collapses and someone’s hurt I’d be up in the dock. So I make sure they’re put together properly. Ditto my boss would be in trouble if I’d not been trained properly in how to put up a scaffold tower and it collapsed. But in that scenario, I’d (probably) be OK as I wouldn’t be expected to know that I needed more training, that’s the job of the person doing the risk assessment and method statement. Doesn’t stop my boss from running a company or me from putting up the scaffold because we both know (and have done the paperwork, and stick to best practice) so we know the risk is as low as reasonably practicable.