Is the first person who runs out and defends themselves to everyone and tells on someone else, usually the most guilty?

If you've observed children playing/fighting, there's always one who runs and tattles first. I think the mentality there is... if I tell first I will look the most innocent and the least guilty.

They feel the weight of the guilt, but that does not necessarily make them the guilty party……often does though.

I'd say a lotta times, true. Kinda like the person who smells the fart first, lol.
It's like a defensive insecure behavior.