I've been trying to get a straight answer on that as it is a misuse of transportation funds to close a transportation facility at night but then again the park cannot be responsible for things that might happen at night and it seems the legals do not have a way of saying "use at night is at your own risk" so they have to say closed at night.

So far I have never been stopped at night and there seems to be a fair amount of joggers using the trail at night, a few stories I have heard that if the park ranger stops you, it is just a warning but lets you ride the trail anyway.